As of today here are my thoughts on both of these drones after extensive flight testing/shooting with both units.
First off,  I think the Phantom 4 Pro and Pro + are great drones.  They really do produce stunning images and there is no drone on the prosumer market that can beat the quality in still images that these drones produce.  Simply put,  for still photographers out there,  the P4Pro is a must have.   The other game changer on this drone is the 4k/60fps.  If you do commercials, indie films, documentaries, low budget music videos and the like,  you can really add a ton of versatility to your image quality with the 60FPS.  Use 4k/60fps,  a filter, and shoot in D-log/Cinelog,  and you will get some amazing results (especially if you decide to slow down your footage).  The image is a noticeable improvement to the regular P4.  
However, with every DJI product there is a caveat.   In the case of the Phantom 4 Pro and the Phantom 4 Pro +,  I have to say DJI made one incredibly strange choice that makes absolutely no sense to me.  So if someone has the answer to this question,  as I have no doubt it has been asked before,  please enlighten the forum.   So....DJI decided to include an HDMI output module as well as an on board SD card reader on the Phantom 4 Pro Plus but NOT on the Phantom 4 Pro.   To me this is an odd move on the part of DJI.  So you have the Phantom 4 Standard..., Ok, this I can understand not having a HDMI or SD card slot on the RC because it's the base model, and often the base models have minimal bells and whistles.  However......When you put out something out that definitively says the word "Pro",  it suggests something more then what it was.   And what it was is still what it is as far as the DJI Phantom 4 Pro's Remote Controller is concerned--not PRO, no big pro integration updates IMO.   The reason for skimping on the HDMI input/output is a mystery that is only exacerbated by the fact that DJI's advertising (of the P4Pro/+)  only seemed to emphasize that the only difference in the two models is the P4Pro Plus Monitor.   And sure, you can spend another $99 dollars and get the "HDMI Module" attachment, but why DJI?  To make matters worse, if you did want the HDMI module and thought you were going to get the HDMI module quickly, you are wrong.  There is currently a 20 day shipping wait.   For those of you who are professionals,  the HDMI module actually is important.  It's great to have for "professional" work.  For example, when doing live broadcasts/feeds or when working with clients, it's important to have a good signal feed.  Ok, maybe I'm being a little fussy about the lack of the HDMI module on the regular Phantom 4 Pro,  however to me this drone should have come with one, plain and simple.  
However,  there is a positive with the regular Phantom 4 Pro and that is the fact that you can connect your iPad to it..... Wait?  What's that?  I thought that the Phantom 4 Pro Plus had this amazing bright new snazzy monitor on it.  Yeah it does, but you heard me correctly,  after hours of flying with this monitor,  and having updated it 3 times or more now,  I can say that the Phantom 4 Pro Plus monitor offers terrible range.  Perhaps if you live out in the country you are having a different experience,  but add a little city life and it doesn't matter what frequency you are flying on,  you aren't going to be seeing anything on that monitor after a few hundred feet (I'll post a side by side range comparison here soon).   Now I'm just hoping I have a defective unit,  however as it stands,  I fly my Phantom 4 Pro when flying over 500 feet out......Yes I said 500 feet (again that's just my experience).   This is a shame because the Phantom 4 Pro Plus has so much potential in the fact that it's a one shop solution.  When working,  the monitor does offer beautiful picture clarity and an easy to navigate screen.  However,  at this point in the game,  the Phantom 4 Pro and the good old 1Pad is where it's at.... The 1Pad setup in my experience is the only viable option right now for medium to long range flights.  PS -  While I was writing this review I went to the DJI store to see the retail difference in price between the 4 Pro and Pro Plus,  however the Pro Plus isn't currently on sale on the DJI.com website.  If I remember correctly, there was about a $400-500 difference.   If anyone knows why the Pro Plus is not currently on sale please let me know.  If it is the reasons I listed below (and on a previous post) I'd like to know.  Regardless,  unless a firmware update is on the way, the Pro + is going back for repairs.  I hope others have had better luck with your Pro Plus monitor.  If so, I'd love to hear about it.  

As of today here are my thoughts on both of these drones after extensive flight testing/shooting with both units.
First off,  I think the Phantom 4 Pro and Pro + are great drones.  They really do produce stunning images and there is no drone on the prosumer market that can beat the quality in still images that these drones produce.  Simply put,  for still photographers out there,  the P4Pro is a must have.   The other game changer on this drone is the 4k/60fps.  If you do commercials, indie films, documentaries, low budget music videos and the like,  you can really add a ton of versatility to your image quality with the 60FPS.  Use 4k/60fps,  a filter, and shoot in D-log/Cinelog,  and you will get some amazing results (especially if you decide to slow down your footage).  The image is a noticeable improvement to the regular P4.  
However, with every DJI product there is a caveat.   In the case of the Phantom 4 Pro and the Phantom 4 Pro +,  I have to say DJI made one incredibly strange choice that makes absolutely no sense to me.  So if someone has the answer to this question,  as I have no doubt it has been asked before,  please enlighten the forum.   So....DJI decided to include an HDMI output module as well as an on board SD card reader on the Phantom 4 Pro Plus but NOT on the Phantom 4 Pro.   To me this is an odd move on the part of DJI.  So you have the Phantom 4 Standard..., Ok, this I can understand not having a HDMI or SD card slot on the RC because it's the base model, and often the base models have minimal bells and whistles.  However......When you put out something out that definitively says the word "Pro",  it suggests something more then what it was.   And what it was is still what it is as far as the DJI Phantom 4 Pro's Remote Controller is concerned--not PRO, no big pro integration updates IMO.   The reason for skimping on the HDMI input/output is a mystery that is only exacerbated by the fact that DJI's advertising (of the P4Pro/+)  only seemed to emphasize that the only difference in the two models is the P4Pro Plus Monitor.   And sure, you can spend another $99 dollars and get the "HDMI Module" attachment, but why DJI?  To make matters worse, if you did want the HDMI module and thought you were going to get the HDMI module quickly, you are wrong.  There is currently a 20 day shipping wait.   For those of you who are professionals,  the HDMI module actually is important.  It's great to have for "professional" work.  For example, when doing live broadcasts/feeds or when working with clients, it's important to have a good signal feed.  Ok, maybe I'm being a little fussy about the lack of the HDMI module on the regular Phantom 4 Pro,  however to me this drone should have come with one, plain and simple.  
However,  there is a positive with the regular Phantom 4 Pro and that is the fact that you can connect your iPad to it..... Wait?  What's that?  I thought that the Phantom 4 Pro Plus had this amazing bright new snazzy monitor on it.  Yeah it does, but you heard me correctly,  after hours of flying with this monitor,  and having updated it 3 times or more now,  I can say that the Phantom 4 Pro Plus monitor offers terrible range.  Perhaps if you live out in the country you are having a different experience,  but add a little city life and it doesn't matter what frequency you are flying on,  you aren't going to be seeing anything on that monitor after a few hundred feet (I'll post a side by side range comparison here soon).   Now I'm just hoping I have a defective unit,  however as it stands,  I fly my Phantom 4 Pro when flying over 500 feet out......Yes I said 500 feet (again that's just my experience).   This is a shame because the Phantom 4 Pro Plus has so much potential in the fact that it's a one shop solution.  When working,  the monitor does offer beautiful picture clarity and an easy to navigate screen.  However,  at this point in the game,  the Phantom 4 Pro and the good old 1Pad is where it's at.... The 1Pad setup in my experience is the only viable option right now for medium to long range flights.  PS -  While I was writing this review I went to the DJI store to see the retail difference in price between the 4 Pro and Pro Plus,  however the Pro Plus isn't currently on sale on the DJI.com website.  If I remember correctly, there was about a $400-500 difference.   If anyone knows why the Pro Plus is not currently on sale please let me know.  If it is the reasons I listed below (and on a previous post) I'd like to know.  Regardless,  unless a firmware update is on the way, the Pro + is going back for repairs.  I hope others have had better luck with your Pro Plus monitor.  If so, I'd love to hear about it.