The idea of a basic Arleigh Burke as a large frigate has been kicked around a bit online.
Take a flight-1, delete the rear 64-vls cells, leaving 32 cells at the front…..
That would leave space for large aviation / mission facilities at the rear.
Go for the smaller, lighter AN/SPY radars like on those Norwegian frigates….
Shave off a load of weight & lots of cost but you still have a large versatile platform with space to spare.
Better if similar in price to the navalised coast-guard vessels.