It seems I have made myself a reputation here as a Baxter simp to be called out like that (not that I mind lol). Anyway, to answer the question, how Izzy feels about Baxter is obvious (duh) while she is quite indifferent to Ren. Ren not wanting to hang out with girls didn't bother her much as she understands that people has their own preferences when it comes to friendship.
Despite Ren initial reluctance, it didn't took long for her to be accepted as part of the club due to her tomboish nature and go with the flow attitude that match well with the trio of boys.