Gravity Dom Complement?

I'm using the double XP weekend to give Dominator a try. I really wanna go with gravity - Any suggestions on a good secondary for it?

If you want to "give Dominator a try", the common consensus is not to pick Grav as your primary. By all means, don't let me stop you from trying something that you think you might like, but I'm fearful you'll test out the AT's most reviled set and judge Dominators negatively based on that. Make sure to try a few different sets, is all I'm saying.

I got a Grav/Psi to 10 and deleted it. It had long animation times and generally felt lackluster. Someone else will fill you in on the rest. Maybe they can resell me on it too.

Like Blasters, Dominators are often maligned by the Scrapper/Bruteaholics as squishies, when the reality is that those players simply don't understand how to play them. Astute perceptions and the ability to move around the battlefield(or away from it!) quickly constitutes your defensive secondary. Doms play best in an aggressive, forward role. They are definitely not a "support" AT.

Don't make the newbie mistake of opening with the AoE Immobilize powers. It turns you into an aggromagnet that will quickly hate playing Dominators.

Honestly? Earth Assault. It has Power Boost, which helps Grav out with control, which it desperately needs, Grav has a lot of ranged attacks, which Earth Assault lacks, as well as -Fly in nearly all of its powers, which Earth Assault needs because its ranged attacks only work on things close to the ground. Seismic Smash can even help you hold a Boss with a quick one-two punch, which Grav would need since its ST Hold has -knockback, preventing you from using Lift to safely hold a boss out of Domination. Grav doesn't have -KB in its other powers, though, and since Earth has a lot of AoE attacks with KB, you can use those to help Grav out with its own lack of control.

Grav is a very late-blooming set, however, and Earth is a very Melee-heavy secondary. They mesh well together, but be mindful of their shortcomings. What ranged attacks you have will all be very slow, and your options for control will be limited before you get Wormhole.

I have a Gravity/Energy Dom that I think works rather well. I always thought that Energy was the closest Gravity has to a thematic counterpart (in the sense of Fire/Fire, Ice/Ice, Plants/Thorns, etc.)

I'll also vote for Grav/Energy. That's my main character, and it's a fantastic combo, although it's somewhat of a late bloomer. You have to treat your dom as a single-target blaster for much of her early career. Pick up Gravity Distortion, Lift, Power Bolt and Power Blast early. Later, when you have access to Singularity and Wormhole, you can change your playstyle a bit to mix it up in melee, grabbing bone smasher and total focus. Skip whirling hands, it's complete moist garbage. This is a single-target heavy playstyle while solo, and when grouped, you'll be focusing on using your controls to keep the enemy team under wraps.

Gravity's got some awesome features which a cagey player can abuse. One, a lot of your powers come with -fly. Now this won't work on some enemies (Longbow ambushes in Mayhem missions, for example), but most of the time it will let you hang above the battle in relative safety as you dispense damage and controls. The gravity immobilizes don't confer knockback resistance, which makes a fantastic synergy with ice/earth controls. Energy is a very complimentary secondary, with knockback helping to deliver soft controls to beef up early survivability, power boost to help stacking magnitude on resistant targets, and solid single target damage to thin enemy numbers quickly, reducing the load on your control powers.

PS: Grab leadership, and in particular vengeance. It's a great teaming power anyway, but power boost plus vengeance STOPS teamwipes dead.