I think most syrian toys would be fine, but like you said don't use platforms or things she could fall from. Maybe later in life if she gains strength and no longer wobbles you could get her some platforms but for now I wouldn't.
Depending on how wobbly she actually is, I don't think she should have constant access to one, in replacement to a wheel she could have a lot of play pen time - she can run on a flat surface then. I like the playpen to be bigger than their cage, so they have more length to run. Make sure she has lots of hiding places and toys in there for her so she can hide if she wants
Some runts live long lives, but some don't. There no real way of knowing how long they will live, but they will always be on the small side and may be prone to health problems. Just try enjoy your time with her as much as you can