Quote Originally Posted by villainsimple View Post
You are aware that that is EXACTLY what the Summon Spells do.
No. In fact, it's not what summons do at all.

Summons allow you to create a monster that will fight for you, but they're insufficient to replace another actual party member, even a plain-vanilla fighter.

Charms are a bit more powerful, because of the relative power of NPCs, but they're still not going to replace another party member.