Help with my Illithid

[Biolink22]

Currently playing in an epic level campaign, my PC is an Illithid wizard (loosely based on the "How to be a Mind Reaver" comics). I'm looking for possible feats or interesting spells or items I could take to help make this useful/fun.
Some pertinent information about my character and our campaign:

Using the base Illithid as my race (not the psionic version)
Basically anything 3.5 or PF is allowed outside of BoED or BoVD.
Using the Exploiter Wizard archetype
Mostly focusing on Transmutation and Conjuration (Teleport) spells for story reasons.
I am the only semi-psionic in the party
I am using the Treeantmonk God Guide but it won't hit/cover everything 3.5/PF is vast
In the case of spells with multiple iterations between 3.5/PF I generally get my choice of which version to take (though Spell Compendium does take priority if there are multiple variants within 3.5)


I'll also note that anything Illithid specific would be great too as I am at a loss finding almost anything at all for them.

[Zanos]

What rules are you using for the Illithid race? Normally being a monstrous spellcaster isn't very effective since full casters loathe losing caster levels. Under 3.5 rules a level 1 mindflayer wizard would be ECL 16, which isn't great.

[Biolink22]

What rules are you using for the Illithid race? Normally being a monstrous spellcaster isn't very effective since full casters loathe losing caster levels. Under 3.5 rules a level 1 mindflayer wizard would be ECL 16, which isn't great.

The basic rules for the Illithid race however the DM did houserule that I could take Practiced Spellcaster twice to at least bring my CL up to my hit die

[Biffoniacus_Furiou]

What ECL are you using? PF has ECL = CR so it's a significant difference between the race being ECL 15 for 3.5 vs ECL 8 for PF.

Do you have the option to use the psionic mind flayer variant? Do it if you can, and take Cerebremancer. Or even see if you can trade that Psion manifesting for equivalent-level Wizard spellcasting.

With Exploiter Wizard you can take the Bloodline Development exploit and pick something like Psionic Bloodline (https://www.d20pfsrd.com/classes/core-classes/sorcerer/bloodlines/bloodlines-from-3rd-party-publishers/paizo-fans-united-wayfinder-magazine/psionic-bloodline/), or any other if you find one that's fitting. The Counterspell exploit is fantastic, take Improved Counterspell as well. You can also take the School Understanding and Familiar exploits and the Exploiter variant ends up being a net gain.

[Edea]

Normally the Illithid Savant (http://dnd.arkalseif.info/classes/illithid-savant/index.html) is horrific cheese of the worst sort imaginable...but given you unique circumstances? This might actually help you keep up with everyone else, as all of those aberration HD and that massive LA's really crippling you for an epic campaign (as Zanos mentioned, you're already 16 levels in the hole before taking even a single level of wizard, and in the epic tier by the time you're able to cast a fireball).

In fact, if possible I'd ditch the wizard part and go straight into Savant, then just go find some normal spellcasters and eat their brains.