I differ with you on the opinion about battleships being obsolete. Perhaps World War Two era battleships are obsolete and I’ll agree. But the role of a battleship in a modern naval fleet isn’t quite yet obsolete any more than destroyers, frigates, corvettes, gunboats, and submarines are obsolete.
I am not an naval architect and will not speculate on what a modern battleship would look like, how it would be armed, and etc. but the experience of the Gulf War should demonstrate that there is yet a place for a big gun capital ship in a modern navy.
I also think a modern battleship would be pretty damned cool !