Bringing more ships into the game will just make it more pain staking. IMO they should just rework caps to only fight caps and structures. This would stop the abundance of caps showing up for sub-cap fights.
Honestly though, this would be incredibly interesting. But why? A good fleet of battleships can easily stop a few carriers or Dreads. IF you fine the solo cap pilot a fleet of Cruisers can even take it down.
Like so
Here’s my complaint about Caps. I just posted it today, it may intrigue you.