One would think some old and new designs could be combined to get the navy a class of true heavy cruisers. Room for current weapons and built for possible future weapons.
As for shore bombardment that could be done with the proven
8 inch gun from WWII. Yeah it is old but it works and was used through the Vietnam era.
The Zumwalt class, ahhh... what were they smoking?
A 16”/50 caliber Mark 7 – United States Naval Gun trumps that 8” popgun, EVERY time!
I doubt the USA has the capability to build a ship that can carry a 16”/50 caliber Mark 7 – United States Naval Gun, but it would be a fun exercise to resurrect the Montana Class BB and update it to modern times! (https://en.wikipedia.org/wiki/Montana-class_battleship#USS_Montana_(BB-67))