I'm starting to think about moving to a new city and was considering to build a tool like this. And now I'm excited to see this already exists!

For my use-case the interface you created isn't the best. Now that I'm searching for a new home I'm interested in finding a place that has a bakery nearby, but it doesn't really matter what bakery. The same goes for restaurants, pubs, ... For this case there are too many places to add them "manually".

Thanks for creating this, I will be definitely using this in the the coming months.

You don't have to add them in manually - the heatmap interface supports "Open searches", where you can add in pins for a bunch of locations at a time based on a query (like "bakeries").