I live in a C1 wormhole, so Dreadnaught ratting would be way too much for me. But I have some knowledge in wormhole ratting, so I’ll try to help you as best as I can.
Yes, XL weapons have the worst tracking, and it’s logical. But, fits with two Tracking Computers II and Tracking Speed scripts are generally enough to solve the problem.
Concerning carriers : you’re going to be less efficient if you use a Thanatos or Nidhoggur compared to any dreadnoughts, because sleepers love to shoot drones, and fighters are bigger versions of drones.
Example : you bring your Thanatos in a Core Garrison C5 site, and deploy three squadrons of Firebolg light fighters. Since you’re going to need special warp in bookmarks, you’re going to sit quite far away from sleeper drones and propably going to use the Networked Sensor Arrays, which mean you have no EWAR capabilities, so the sleepers will never target you first compared to your fighters dealing massive damage.
As you can see, each wave in the Core Garrison have warp scramblers and Stasis Webifier, even more, the second wave have RR frigates, which mean if the rats lock your drones, they will shut down their MWD (with the scrambler) and slow the fighter down to a point where even battleship sleepers will track them. You’re going to lose squadron after squadron, and fighters cost a lot, plus are hard to move in a wormhole if you don’t have an Azbel with capital shipyards.
To conclude : fighters and thus, carriers, aren’t viable in high tier wormholes.
Also, if you’re using a good fit, you can finish the site in two siege cycles, and the Revelation dreadnought do not consume ammo if you stay with T1 crystals, which is a lesser cost.