One of the things the game is missing IMO is a satisfying projectile weapon. Clicking on heads is fun, but it's not the same as adjusting for distance, leading the target to account for motion, timing the release, and then landing a perfect headshot.
But I think we have most of the tools to make it happen. You can currently hack together a passable "bow" gun.
Start with a 2-handed ballistic weapon.
Have it shoot a copy of the Auto Rivet projectile. Maybe at double the speed because that's still a bit slow
Possibly change projectile type to Arrow (from Missile)? I haven't noticed a huge difference
Change projectile's gravity affect down a bit to make it float a bit more. It's 1 by default in Starfield. The Fallout 4 bow mod used .35
Ammo size is 1
Bolt action (I think this does some things with the animations that basically covers the same time window that drawing another arrow would)
Charged shots (~0.3-0.6s) with a minimum charge of 0.3
After that, tweak all the accuracy/projectile/power numbers and anim speeds until it feels right.
Optionally: put together a nice circular pin ironsight for it to help with judging distance on shots.
I did this with the Auto Rivet and it was going great. Felt very bow-like, but then I tweaked it too much and screwed it all up and can't get it to shoot straight. Might try again some time and publish if there's interest