No specific recommendation per-se, but I can guide with:
- looking at F-droid packages, in the first place to narrow down decent candidates
- then inspecting the source code of the select project by checking: commit history, if releases do export an
.apk, seeing if the project is still alive (frequency of the updates, repo’s issues) - the amount of permissions/trackers it does have
- [optional] double-checking how it behaves with no Gplay, good apps don’t enforce it on your usually
The rest is more about maintainer’s street cred + features of the app itself given your subjective taste. 
If this is the Simple Radio we’re talking about, it feels quite clean + fine given the list above with no big red flags[1]. 
even if the maintainer has not enabled the issue on that repo, he is still reachable by email + they allow it on their other projects ↩︎