It really depends on which one you are planning to fly (though dreads and carriers share a lot the same needed skills) and what you plan to do with them.
For a dread they are POS bash mobiles and for use against other caps. They can't hit shit if a ship isn't cap size unless it is painted to hell and webbed.
Carriers, you get some options. If you are going to use it for PvE then you can play to whichever carriers strength they have, but for a cap fleet you'll have to armor tank.
Basically for either of them you'll need your armor tanking skills high as well cap repair. For carriers you'll need cap RR and excellent drone skills across the board. Dreads you'll need excellent gun skills.
For most people caps aren't worth it imo and you probably wont be using it as much as you think unless you are running anomalies. If you are in an alliance that supplies the cap during a CTA then it is worth it but for the average person na.
IMO ichy, since you are use to smaller ships just work your way up slowly. Get comfortable with a BS as the skills used for that will transfer over to a cap anyways. Or start looking into other ship types like a HAC. All depends on what your goals are.
Caps are nice but they have limited use really and for pvp situations you really need to be in the company of a couple of other caps cause otherwise everyone and their mother that knows a single cap is around get a fleet together to kill it, everyone loves a cap killmail
