She's definitely overstepping. While it's nice of you to consider her ideas, it sounds like she's taking advantage of you. I might back off on even doing that, at least for awhile.
A couple of years ago I had a para who thought she knew better than me and made that quite clear. She was always trying to go off and do her own thing. I tried to speak to her privately and she just didn't listen to a word I said. Finally I had to start correcting her in front of the students. "Para, the students need to be doing their letter cards right now. Please get those out. Para, the group was over 5 minutes ago and these students need to be back to class (she couldn't follow a schedule to save her life). Students, line up." She'd try to argue with me and I gave short answers that definitely sent the message that the conversation was over.
She and the other sped teacher seemed to love each other. One day I finally asked the other sped teacher what in the heck she was doing to make his para effective in her room. She said, "Oh, I don't let her near students."


. Come to find out, she was only having her do things like filing, copies, cutting things out, making flashcards, etc.