Decent backpack. My backpack is simpler, holds 5 batteries, laptop, charger, spare props, various cords and my tablet. A bit of room to spare.
As for the prop bolts, you know those swimming pool noodles? They come in small sizes too. Get one of about 1 inch diameter and 2+ inches long thereabouts. When you cut this length into 4 equal pieces, you can push these pieces onto your prop bolts. This will ensure they don't push holes into your backpack fabric over time. Works a charm.