So the monolith... IS it too powerful?
It's my favorite support ship by far, but it's also something I never want to pilot. The universal slots make it ideal for mounting insane support weapons like LRMs or whatever long range cannons or beams are available. It also has HUGE costs, to buy, to bring, and to deploy. It also fits a lot of roles at the same time, with great cargo and crew capacity as well as the autofactory support.
A well equipped AI monolith can easily 1v1 a default sim Paragon (and maybe a couple of his destroyer friends at the same time). It all depends on the equipment of course, but that comes back to the universal slots giving you access to everything worth having.
If the slots weren't universal it would be a LOT weaker. One of its strengths right now is to be able to put everything into a single strategy, if it were forced to generalize more instead of minmaxing for a single approach it would actually struggle to keep up in battle.
I don't really know if I would change it, but in my personal opinion I would class it a tier 1 or 2 ship easily.