Sort of a side track or bunny trail. By Battlefield do you mean Battlefield 4? Never played any version of Battlefield. I thought it was FPS game (Sniper type game). Recently heard that it has tanks. So I am curious.
Battlefield is low on the realism but very strong in a game-world combined arms. It's mostly infantry FPS, but you can spend your entire time in various AFVs, planes, helos and boats. IMO it's got much higher skill requirements in terms of conventional gamer skills than WOT, even in the highly simplified vehicle mechanics.
WOT is slow, BF requires you to be fast, map aware, know how to work the team mechanics, etc. And be a fast/accurate shot.
The AFV combat is limited, there are only a few weapon loadouts and only 3 types of truly armored vehicles. Armor angling is now a feature as well.
If you've never tried a BF game, you really should.