Abel and Rufus are my 2 mains.
Abel was my first main and still the character I'm best with, but he has very serious drawbacks. Most notably a lack of a reliable anti-air. If you're good with applying pressure you should be good with Abel.
Rufus is a different beast - his whole gameplay revolves around landing his Ultra off just about anything.
A few Ultra setups, just off the top of my head:
1- lk -> rh -> Ultra
2- j.rh -> Ultra
3- j.rh -> EX snake -> Ultra (corner only against some people. heh)
4- f.Galactic Tornado -> Ultra (corner only)
5- EX Messiah -> lk followup -> FADC -> Ultra
The fun thing with that is that lk -> rh and EX Messiah are SO INCREDIBLY easy to land that you'll almost always pull off an ultra in any given round. lk comes out very quick and can be used to easily punish just about anything.
Another thing to note (since I've seen you mention it) is that you should never rely on Abel mk crossup -> c.hp. There are a LOT of problems with that, unfortunately. If you do the crossup too soon, your opponent will recover before the first hit of the c.hp hits. On a lot of characters, the c.hp will only hit once (especially if they're crouching). It's not incredibly reliable, especially online where you'll be SRKed/SPDed out of it quite often
He does have a few things going for him though.
1- His ultra does MASSIVE damage, especially on a non-combo hit.
2- His Super is godlike (LP super is hit invulnerable, MP super is throw invulnerable)
3- Relatively easy for combos into CoD
4- Many traps, ways to apply pressure
5- Wheel Kick is a great way to keep players at bay and to outpoke turtles
6- Jab tornado throw beats ANY throw in the game, including Gief's Ultra. It also has great range and general priority. I love fighting Balrogs now since any time they do a non-short dash punch they get TTed. EVERY. SINGLE. TIME. If I see a EX rush, TT. If I see a normal rush that goes further than midscreen, TT. It's that simple and very easy to do on reaction.