Rebalancing via era doesn’t solve anything & will still be far worse than the current game.
If you wanna see what I mean just take your Clemson class or Wickes class (heh only one in game is a Town class 1940 destroyer) & bring it to 6.3 with your WWI Dreadnought & see how your battle goes, aka pretty shit mate.
Even if you made stuff to date all your WWI / interwar vessels would get shafted by WWII/ late WWII equipment ntm most post WWII vessels are armed with WWII designs & surplus equipment eg the 3"/50 Mk. 22 cannon for the former & the 40 mm/60 for the latter, not sure how fun that would be if those weapons were done by dates eg 1968: as RIP HMAS Arrow P80 facing the JDS Chikugo DE-215 & SKR-7 lol an only the latter has nasty mid cold war guns while the rest are WWII guns (RUR-5 armed with W44 for Chikugo class when?, I want my sea nukes).
GF equivalent is essentially taking the PBV301 up to 7.7-8.7 BR or taking the M41D up to 12.0, would you wanna see those matches if done by era?