I agree, Paris is wonderful for either in-person or virtual walks. Most cities have large pockets of uninteresting zones, but Paris rarely has that. In the dozens of times I've been to Paris in my life, I have usually found a whole new cool small street that is often just 20 meters off a more trodden street. My obvious technique is to pick two points in the city and try to walk as direct as possible between them, forcing myself down side streets instead of walking down some grand boulevard for an hour. -- as I walk I'll put a star in my Google Map on anything interesting that I find so next time I'm in the area I can see that it is around the corner.