Wow.
Bethesda would get to comfortable adding gun grips and camiflauge and underrail shotguns, and move away from quality writing and rpg elements. We really don't need rds scopes and advance army tech in the next game.
Rds would actually fit fairly well in the series, heck there was goin to be one in FNV but it got cut.
As for what mods I would like, I'd like some Armour mods and More weapon mods.
Maybe find schematics of modifications and the like, expand on the already stellar crafting system from FNV (and bring back the damn craftable weapons!).
As for mod ideas I'd like to see implimented...
-Modified Muzzle Brakes for higher caliber Sniper Rifles.
-Modified stocks for rifles, ARs, SMGs, shotguns.
-Shell Slings for shotgun stocks (faster reload).
-Bipods for Sniper Rifles and LMGs
-Variable Zoom Scopes for SRs
-Modified Bolts, Actions, and MAg Sizes for most weapons
-Extra Plating for Metal Armours
-Extra Padding for Leather Armours/Raider Gear/Light-Med Armours
-Enhanced Targeting devices with certain helmets (PA, Advanced Combat Helmet [HUD?])
-Recyclers for some Energy Weapons or another efficiency mod that works with EW
-Beam Magnifiers for Laser weaponry
-Particle accelerators for Plasma Weapons
-Capacitors for Pulse and Tesla Weaponry to enhance the energy they fire
-Environmental Protection mods for most armors
-Rebreather integration with PA and/or Combat Helmets