OK, if you want to develop that idea and pitch it to the Pentagon, then I sincerely wish you good luck. But modern military designs (
including naval vessels) have been transitioning more and more towards stealth, and that involves minimizing their surface area in order to reduce their radar profile. The new F-35 is specifically being pitched as a stealth fighter that can evade interception by Russian S-300, 400, and 500 SAM systems.
A gargantuan weapons platform with the ability to shoot down incoming rockets sounds nice. But shooting down fast-moving missiles with small radar cross-sections, that can arrive from multiple directions, and that may even travel with a complement of decoys, presents serious complications for the design of point defense systems. Garish mega weapons like these, that do nothing to minimize their likelihood of detection, don't personally strike me as the safest investment. It would be cool to have the contemporary equivalent of a Super Star Destroyer, I'll give you that much.