If you're gonna make a game then UE4 would be a great engine to use IMO. I used to do a lot with UDK back then, not that I ever made a game, I just used to make levels using models I made in 3DS Max, I could never get anywhere AT ALL with programming so I gave up in the end (no point keep making levels & models if I can't turn it into a game, its just a waste of time).
So I'm long past trying to make games now but given whats possible with cream of the crop engines like Unreal, I know you could do something amazing with it. Speaking of Unreal, I can't believe in over 20 years of Unreal Tournament, and all the 1000's of mods like skins, new characters, maps, game-modes, mutators, weapons etc, there NEVER seems to have been any adult mods except nude models. Never any animation based stuff. I always wanted to see somekind of mod where bots could fuck you (or any other bot) if you/they get knocked to the ground or lose enough health, and you could do the same to them, for some kind of bonus, maybe like Udamage lol. Even an XXX version of Capture The Flag (Capture The Slag) would've been sweet...