All of TM data is available
on GitHub but the formats were built for TM (and previously CHM) tools.
I think what you want is to bring up individual routes in the Highway Browser or in a regional mapview. You can see the route(s) on Google Maps or other tile sets there and if I'm traveling somewhere new or just somewhere I've been but am interested in finding some new way to go, I'll often have the
mapview for the region where I'm traveling displaying my current data loaded up on the iPad.
One thing we're missing, which I don't think is hard to add but I've just not had the time to investigate, is that blue location dot on TM's maps. It's on the list.
I don't think you want to rely on just the TM data, now or in the future, for detailed directions. TM's route data is intentionally relatively sparse. Especially for a route that bounces around a few streets through a downtown area, we'd include only those that are major intersections plus any needed to keep the route's "line" reasonably close to the route. There's also the issue that we typically split down the middle for routes that are a one-way pair through cities. Our data also only has the route names/numbers we encode for the files, not street names.