You're right, absolutes are problematic. I changed Impenetrable Illusions to mimic Insidious Casting so it's more fair. I also removed "Supreme Flank" and replaced it with "Supreme Two-Weapon Fighting."
I copied the formatting of DragoonWraith's excellent
Invoker class so there's an easily referenced chart. I also took one of his invocations,
Falling Dream, but swapped it from Lesser to Greater for my purposes (I felt it would be too strong as Lesser).
The class isn't done yet, but it's almost there. Probably needs a few more invocations. I just hope it meets my goals of:
1) Fun
2) Not overly complicated
3) Low-to-mid tier 3