Do you need geocoding? I ask because I am one of the makers of the OpenCage geocoder. We offer forward and reverse geocoding from open data (primarily OpenStreetMap, but also others). We're listed in the migration guide, and we'll be offering 20% off our pricing for all former Mapzen customers. Blog post about that is coming shortly.
I hope we can help you.
https://geocoder.opencagedata.com
Edit: here's the post about the 20% lifetime discount for former Mapzen customers: https://blog.opencagedata.com/post/mapzen