The spell-like ability evolution does not say what the spell-like ability's caster level is supposed to be...what's it supposed to be?
Also, what languages do eidolons know?
The language question was answered somewhere hip deep in the Summoner Revision thread. I know for sure they can speak a language in common with the Summoner.
I'd say caster level is either HD or Summoner Level.
The Eidolon's caster level is equal to the Summoner's. This was also stated somewhere deep in one of the questions thread early on by Jason. As others have said, the Eidolon knows every language the Summoner does, plus any languages it learns from ranks in Linguistics.
Eidolons get FREE evolutions based on their base form. Every level, a summoner can switch out his eidolon's evolutions as he sees fit.
At 2nd and later levels, can a summoner switch out the evolutions that the eidolon gets for free to get a few more points?
For example, it would make more sense for a "giant floating eye" eidolon to have a slam attack, but no bite attack, to have a fly speed, but not a walking speed. Unfortunately, all the base forms have either legs or a bite attack. It would suck if the rules stuck you with them (since roleplaying should be about more options, not less).
No. You cannot switch the evolutions the base form grants.
No. You cannot switch the evolutions the base form grants.
Well that limits creativity, doesn't it?
I guess I can have my eyeball eidolon roll along the ground for land speed and "bite" people with its eyelids.