I haven’t read either book, so I’m not sure if Enders is worth reading. However, I think if you really liked Starters then you should read Enders. Typically if I read a book and really like it I will read the sequel/s, but if I didn’t like it that much or just didn’t care that much about the characters or story then I won’t. Even if I see/read bad reviews about the sequel I often read it anyway just because I liked the first book so much.
I don’t read many romance novels, but I can recommend a few fantasy/paranormal romance books. There’s Starcrossed by Josephine Angelini and The Goddess Test by Aimée Carter, and one I’m looking forward to reading is The Kiss of Deception by Mary E. Pearson. Sorry I can’t be of anymore help, maybe someone can recommend something for this lovely anon?