Particle_Man is being a troll. Ignore.
Wu Jen + Alienist seems like a fine combo, with lots of good flavor to boot. I might wait longer to enter the PrC than I would as a wizard, though, to pick up elemental mastery and maybe another spell secret before venturing off into the Far Realm. Or maybe interleave the classes a bit.
The thing that would really set this character off is your choices of taboos. You gotta think of some good alien taboos, like
- never looking up
- being completely nocturnal
- subsisting entirely on blood (choose a "flavor")
or what have you. Let the alienist flavor bleed into the wu jen, and for the Old Ones' sake, don't dress like a friggin geisha!
<tangent>
I started another thread on this subject, and no one bit, but I can't see any reason that an alienist/archmage couldn't turn the Extra Summoning into a High Arcana Spell-Like Ability. That's a nice trick, to basically pay one wu jen fifth-level spell slot plus that freebie alienist slot for two floating highest-level summonses per day (with no components, either!). So you might keep an eye out for archmage after alienist. You'll need to take another Spell Focus and that blasted Skill Focus. Maybe your DM would let you trade one of the "toughness" hit point sets (mad certainty, insane certainty) for Skill Focus (spellcraft) instead. If you
are considering archmage, then make sure your choice of wu jen element and spell focus feats mesh well with the archmage's schtick, like mastery of elements and mastery of shaping. If all this is too complicated, then dump it.
</tangent>
Wu jen don't get a familiar. Are you planning on Obtain Familiar or are you just going to ignore the alienist's familiar abilities/pseudonatural familiar? Probably just ignore it.