I had a chance to try your server. My observations:libosmscout is no masterpiece of cartographic rendering -- upsidedown labels, all kinds of things overlapping -- but I guess that was to be expected. There's a huge difference in rendering time between using a Mapzen metro extract for the Helsinki region and a Geofabrik extract for the whole Finland. So, your desire for users to be able to have databases of arbitrary regions instead of country extracts makes sense from a speed standpoint as well. With a Mapzen metro extract, the rendering time is surprisingly fast -- it's very usable! The large tile size seems fine. I doubt we need the smaller ones. The search seems very particular about the query format. e.g. "Erottaja" works, but "Erottaja, Helsinki" doesn't, "Tukholmankatu" works, but "Tukholmankatu 3" doesn't. The "admin_region" field in search results and thus the description field in Poor Maps is often empty. I can't conclude from the results when or why. The Nearby search seems to work fine, expect for the missing region data, which is a known problem. The raw OSM data is really bad for this though -- it's incomplete, outdated and very particular about how exactly POIs are tagged.