So now I need to have my phone ping GPS periodically (which takes longer without wifi for guidance) to check my position so it knows whether it can scan for access points it knows?

Personally, I think I'd rather just have it scan for access points. Apple's MAC randomization has the right idea (if perhaps an imperfect implementation)

You can use Smarter Wifi Manager but its average at best. It uses Cell IDs to ascertain approximate location.