I recently started playing USF4 and try to get good at it. However playing one game for like 3 or 4 hours each day might let me burn out quite fast so I thought about picking up another FG. A 3D one. One I van have fun with without studying it intensevly. I thought about DoA5 or TTT2. Can you guys suggest me one of these? Or even another?
What I like about 3D fighters is that they are more realistic than 2D Games. I recently watched the anime Kenichi and got interested in hand to hand fighting games because of it 
You have options, soul calibur 2 HD
The Sega am2 games.
Fighting vipers
Virtual fighter 2
Sonic the fighter
, Majority of the namco license fighter are pretty easy. ( jojo all star battle, saint seiya, naruto. Ect)
Theirs…girl fight…its…simple…
Digimon all star rumble, face breakers( no netplay
Are you open to 2.5?
Battle fantasia,
Shin kohime fighter… Import
You also have weired simiators that acts like fighters.
Deadly warriors series
The free to play sparta game.
Out side those your going to have to compromise with import titles, older gen games, or 2d fighters
Ehrgeiz