What's the issue with phase spiders?
Ranged poison attack. They can Ethereal Jaunt at will and attack you from ranged instead of having to actually bite you.
What's wrong with the gnoll archers? I haven't met the minotaurs yet so can't comment on those.
They share the same problem as minotaurs and a few other encounters : enjoying too many actions per turn w/o actual reasons (no racial traits nor any buffs).
Anway i do keep in mind that this is an EA and that some things will change. But i also doubt that these kind of "issues" will be changed as it is not results from a mistake but something they wanted to do.