So initially I was a big fan of Contagion being SMN ability, but I feel that would tip the scales in a quite decisive direction towards Ifrit and essentially make him unbeatable to an extent.
If SMN Contagion affects Ifrits Enkindle? That would be silly.

Also Garuda loses essentially the reason to use her. Aside from a fight like T9 where the boss moves around a lot and jumps all over, Ifrit would trump her in every single fight. She would need a massive buff to compete at that point.

The only use for Garuda would be one of two, in an enviorment where magic is utilized (T11) or fights that are dangerous to receive damage at melee range/ fights that have a lot of arena wide movement of the boss.

Titan, I feel definitely needs a Provoke. However this is something you have to be careful with because it can potentially be quite op, by allowing tanks to dodge mechanics. Imagine how much pressure is removed if a titan egi which can resummoned endlessly, can provoke a mechanic like ravensbeak in T9 savage or Revelation on T12 or Ahk morn on T13.
So perhaps a Provoke with a 3-4min CD or some restriction on it.

As for Ifrit, he does not need a buff.

An old suggestion was to give SMNs a passive party wide buff depending on what PET they have out, and while I love the idea, I feel that could also tip scales further in Ifrits favor.