Oh my, good ideas for once.

Here's what I'd do.

Ifrit - Make radiant shield greatly lower the damage of the next attack it takes, and give it a short cd. Like 20 seconds. This way his inability to dodge aoes isn't as big of an issue, you can pop that if you're watching him well. or completely replace it with a Dot that wouldn't mess up his attack delay
Boost the potency of his auto attack or main attack, or change his formula to boost his damage a bit, or add a low potency dot to his main attack. Otherwise he's still inferior to Garuda in every way.

Titan - Some kind of stance would be good, if you want to use him outside of tanking. I also think he could use a provoke if they ever want him to be taken serious as a tank outside of solo content or a clutch when tanks die in an instance. His aoe enmity move could use a lower CD if he ever wants to tank more than one thing.

Garuda - She does have a ranged AoE. And she's pretty perfect as she is. IF they want to make any other egi viable they'd need to do something with contagion though. Give it to us and give her one of our moves maybe