Battleships are useless solo, but extremely powerful in fleets.
The power of BBs increase exponentially for every ship that is supporting it, imagine a wall of flak gunfire against 1-2 VHF who need to
1: Aim torps
2: Dodge fire from the next 3 ships
3: Evade the fighter screen
4: At the same time :p
If you want to do solo play, I reckon Cruisers are better since you can dod