What I'd like to see: The player's HUD is provided by the PipBoy or a Power Armor helmet, so when you start the game without a PipBoy, you don't have the HUD. This in turn leads to EMP grenades disrupting the HUD; for example if you get hit by an EMP charge, the HUD flashes and disappears, the you get an on-screen message reading something like: "Rebooting". And Power Armored characters could be temporarily paralyzed by the grenades, not damaged more. Power Armor should be harder to find and more powerful, so there should be a very hard quest to complete to get the PA training. But, when you finally get it, you really feel like a walking, one-man tank. First-person view should change accordingly to the headpiece you're currently wearing: like a Power Armor visor and such. More weapons, especially more of those made post-war. I'd also like to see weapon crafting (the Railway Rifle!), as well as crafting other items, such as Weapon Repair kit or the Doctor's Bag. The factions: For once, I'd like to actually join a faction, not merely be a merc hired by them or a random guy that just happens to be working for them. Then, maybe advance in the faction's ranks. I always wanted to be a BoS Paladin. The sprint button, of course. Dynamic quests, a bit like in Skyrim. Bounty quests; quests that require you to retrieve a certain item, but the loaction changes, so you don't have to go to the same location twice. Better NPC behavior. This could be things like: when you walk around a town with a weapon unholstered, people comment on it; or when you actively aim a weapon at someone, you could get a warning or even get attacked for that. Bigger weapons' intimidation. So, when you walk around with a missile launcher on your back, people treat you with more respect. And raiders actually run. Imagine, a Power Armored guy with a Grenade Machinegun walks into a Raider camp. Even the stupidest Raider would know that attacking this guy with whatever scavenged weapon they have will result in a swift death. More chems and better chem effects, not just some stat changes. Psycho could tint your vision red and faster heartbeat could fill the character's ears. Mentats could make everything sharper, the colors more vibrant, sounds sharper and such. Or that could be Jet. And the withdrawal effects, such when you're not on Mentats, everything is slightly blurry and grey. The NPC's could also comment on that, for I believe that someone who needs his fix shows it at least a bit. Combat: - when you cripple a limb, the character should react accordingly, for example: you shoot someone in the leg and you cripple it, so the guy drops his weapon and grabs the leg, seeking cover to bandage it. - the grenades could leave some after-effects, such as ringing in the ears, temporary blindness, maybe screen shaking. - Cover. Hiding behind walls, firing when not looking (you know, you stick your arm out of the cover and fire blindly), indirect grenade throwing, cover that can be punctured: for example, when you fire at someone hiding behind a metal desk using a 9mm pistol, it's useless, but when you use an anti-machine rifle, the bullet pierces the desk and maybe even the guy, making a hole in the wall. - grenade shortcut. - maybe using guns as melee weapons, so when you suddenly bump into a guy, you could smack him with your weapon's stock to stagger him, and then shoot him. Now, some things that might be just a little bit too much, but: - destructible environment. At least by the more powerful explosives and energy weapons, such as the Fat Man, Grenade Machinegun or plasma weapons. - energy weapons ammo. I always found it odd, that when you fire for example the Laser Rifle, you change the microfusion cell every 24 shots, but your MF cell stock is reduced by 24. That would mean that the rifle has one cell connected, but it uses up those in your inventory. I'd like it to work in a way, that every energy weapon uses a different amount of energy for every shot. So, you could have 2 MF cells in your inventory, which could mean that you can fire a Laser Rifle 48 times or a Gauss Rifle 2 times.This would also add some realism, for when you reload only a partially empty cell, it goes to your inventory partially charged, so when you load it again, it has only the amount of energy left when unattaching it. - choosing the PC's origins. You could decide whether your character is from a Vault or maybe a guy born in the Wastes. That's all I can think of right now.