Size does not matter as much here, though I don't know a great deal on Capital ships, I know the Dev team works long and hard on making things balanced. So yes, you won't be able to win all of your fights. If used right, you will be able to win the ones you are supposed to.
Plus, re-balancing ships is hard. It will only happen if it is a huge problem.
its op as it is, save for size. the forward gun is ridiculously powerful and it can mount 6 primaries, so if you go all primaries+cerberus, you can nearly take down a bs shield from the distance with the forward gun and then rush in for the close combat kill, firing everything you got. i find against snubs it performs ok using turret steer and max zoom and just mix up movement randomly at max speed - the turret placement and firing arcs are decent from most angles, so you can keep pounding on your opponent as long as he is within range. i managed to fight off two skilled nova bomber pilots using 8 x secondaries and 2 x flaks without having to use bots. its a good ship.
its a huge ship, but the turret placement is a lot better than on a lot of other battleships, so you got most of that big thing covered, and if you use turret steer and move around, it will be extremely difficult for your enemy to keep ducking in your blindspots for long enough to do you serious damage - problem is if they shield run, you cant really do much about that in a BS, but luckily most people play with honor.
the way you look at BS's,,,is PVP side. Basically each Battleship is good. but how to use it is another business. and you need to RP with VAlor. not to PVP hunting.