Sorry if my comment didn't sound appreciative. It's just that over the years you see many such "added benefit" services added on top of MaxMind, most of them promising to eventually build their own database. And most of them disappear again after some time. It seems to be a tough market. We've looked into this ourselves actually in a project, and it is far from trivial to get to the "accuracy" of MaxMind, with everything they do to enrich and improve their data.
Timezones, currency, etc, might be an added value, and there might be a market for the convenience you add. Your timing might be better than others, who knows.
I also understand you must have put in considerable effort in what I would still call a "frontend". I wish you best of luck!