I can put 1 RG female with.......?

I have one ruby green female and I'm not planning on getting any more for several years. I hate to put her alone in a 10g so what could I put her with?
Moorii (20g long)
Red top lawandas (20g long)
Crested goby (20g long or possibly 10g)
Are any of those combos feasible? I dont want to end up with any hybrids nor do I was to have aggression issues. So what can I do?

You would probley be ok putting her with Moori or your red top

I think I have decided to put her in with the goby in a 20g long. I think I don't want to put her with other cichlids in case it is some kind of parasite that was killing them off. Also at this point if the goby eats her that's fine by me, but I think they will just claim their respective ends and do fine.