I'm currently running Expansive Mind, Demon's Pact, and Sturdy on my Titan and having a lot of success. For majors, it's a lot more flexible based on your group composition, but I really value Juggernaut for the HP increase and the CC Immunity, as well as the Resolve increasing retaliate. Getting CC'd is how you die for the most part, so reducing that is good. If you are in a group already with Jug, there are lots of other options to choose from. Consider:
- Elementalist: Good ground AOE, and the ability to heal off of common confessor fire damage.
- Force Mage: The barrier passive is pretty strong, and being able to push people around is very nice.
- Shield Breaker: Deal more damage, knock over barrier generating classes, pretty solid cookie cutter disc.
- Mole Hunter: Catch stealthers, provide more buffs - only really useful while ganking and small scale stuff.
- Rune Caster: Great group buffs.
- Escape Artist: If you aren't running Jugg but someone else is in your group, run escape artist and be super fast and help clear CC on your group.
Ultimately disciplines are a way for you to make tweaks to your classes play style to suit how you want to play - so just test a bunch of stuff out and see what you like. Good luck!