Mystic Theurge Optimization - Iron Gods four-man party

[Uncle Fred]

Hi folks! I'm preparing a character for Iron Gods and I've been gravitating towards playing a Cleric (Eclesitheurge) 3/Sorcerer (Wildblooded, Empyreal) 1/MT X, using early-entry SLAs to qualify as early as possible. We are a four person party and the other roles so far seem to be a gunslinger, a sword and board fighter, and an alchemist. I've been itching to make a solid MT. I understand that it might not be on the razor's edge, but I'm trying to build as solid of a buffer/debuffer/healer/blaster as the MT will let me.

With that said I have some questions:
-It's been said that a Clr/Wiz MT would need to buy his wizard spells since he's not progressing in wizard. Does that mean that the sorcerer wouldn't learn new spells every level?
-Is it worth considering to tack on the Crossblooded archetype? If so, do you have any suggestions as to what bloodline would fit?
-I'm aware that I'm going to lose out on Class abilities, caster level and a level/three levels of spellcasting (depending on the base class considered). Would I lose out on anything else? Is it that detrimental? Any ways of minimizing it? Will it hurt the party (I especially worry about that since we're only 4)?

Thanks for your time.

[Eltacolibre]

sorcerer are different, they still get spell known but you don't get any bonus bloodline spells because you aren't a sorcerer anymore.

As for bloodlines...not really anything to suggest, you aren't going to get a lot of benefit from just one level of bloodline.

I wouldn't crossblood, with a MT build.

There is a trait I believe to increase your caster level for one class, forgot the name of the trait. As long as it doesn't go over your HD, can help catching up a bit.

[RumpinRufus]

Magical Knack (sorcerer) would be the trait to keep your sorcerer CL high.

[AndIMustMask]

for blasting: grabbing any two of draconic, orc, and primal via crossblooded can really amp up your output.

from what i've seen (both my own reading and on the forums) is that ecclesitheurge is kinda lackluster. then again with the sorc/MT levels it might be alright since you need to worry about ASF?

any deity with the magic domain can grab your the arcane beacon ability, and you can take the theurgy feat to trade arcane spells for buffed divine ones.

you'll definitely want to look into the false focus feat (maybe consider the razmiran priest sorc AT?)

[Trahir]

If you're using early entry anyway and are wanting to get into MT as early as possible, you can actually do it at 4 instead of 5 depending on the race you're using. Offhand I think doing it requires Aasimar or Tiefling, but there may be a couple others that also work.

[AndIMustMask]

drow magic half-elf works too (envoy half elf might, i havent checked the SLA levels). there's a whole guide on early entry shenanigans.

you can get in early on the cleric side via the fate inquisition (or the trickery domain i think).