tbh it's slightly less about the numbers out there for me, more about the potential for misuse.
Ultimately if you have more caps you should be able to win engagements like POS-bashing battles, but not just hotdrop them into any situation to give you the advantage over another (better specced) fleet.
Few ideas off the top of my head (along with the "Jump Drive Stabilization" penalty thing before):
1). Limit caps to only being able to attack or assist smaller ships within a certain radius of a POS / station (or if targeted / aggressed) otherwise their combat modules and drone bay are offlined. Or something. Stop them being dropped into fleet ops in open space and being left there to tank / rep.
If you're going after SOV you should have a fleet set up in such a way as to take caps into consideration.
and / or
2). A new ship. But not another cap. A smaller BC perhaps.
The Mongoose (patent pending).
Something that is specifically designed to attack caps, but only caps. Can only target ships above a certain mass for example. Would need to be balanced so that caps aren't completely removed from the equation obviously.
Take several of these out into your fleet for protection against cap blobs.
Making another bigger ship is dumb as it'll take forever to get into circulation. Having something smaller and punchy can make a discernable change to the game sooner rather than later. But it'd need to be done right.
There's been talk of it already, and CCP have a habit of getting balance wrong so may not take off.
idk, just thinking out loud.