I used to always recommend that people buy a gun for its externals and features that they like, and the internals can always be modified, tuned and improved upon. Krytac has some selection of externals, but the internals, aside from one or two things are on the same level as many upgrades.
G&P has all sorts of external configurations and options, pick and choose to your liking. They are usually a little cheaper, so they allow a little leeway for upgrades. In general, it's just a lot cheaper to buy a rifle with the majority of the externals you want than trying to rebuild it by piecing every specific part together.
For improvements for companies to include from the start, I would love to seem more companies include Neo magnet motors and O-ring nozzles. Some stock guns have buckings that have a split mound, so essentially 2 points of contact. The Krytac bucking is a little more than the "W" hold. It's pretty much a split (split in the middle) with splits on each side of the central split. So 4 points of contact as opposed to 3 with a "W" or 2 with a split, or 1 with a classic stock design.
A flat hop to come standard would be nice, and much more realistic than an R-hop. R-hops are just too unique each install to each barrel. Flat hops are a little more generalized and can be easily accomplished just by sourcing a different bucking manufacture, or changing to moundless buckings one way or the other, along with sourcing some sort of flat nub.
