What to do in OSM once my local area seems to be complete ?

It is a legitimate question we can hear frequently from people arriving late in the project or just contributing on their local area and the area looks pretty well mapped.
You say that the places you know seem complete and it is a very good approach to start with the places you personnally know. The next question is "what to do next ?"
- first, one of the major challenge in the futur for OSM will be to keep the data up-to-date. So, always keep an eye on the places you mapped and report the changes from time to time. You might be surprises by the speed of changes in the time, especially in urban areas.
- next is to check what you consider "complete". Perhaps you are just limited to streets geometry and their names. Then check if you can improve navigation and see if you missed traffic lights, oneways, give ways, etc. Then check if you can improve localization by adding addresses. Then check if you can add the facilities (or amenities) usefull for the public or people arriving to your area like hospitals, pharmacies, doctors, schools, etc. Or what can be useful for tourism like hotels, restaurants, information points and so on.
- then, you can surely use your skills to help outside of the places you know. We have the HOT group helping to map areas after disasters. You can also fix map errors reported either by automated tools or by simple reporting tools like OpenStreetBugs. Many of them can be fixed even if you don't have the local knowledge. For instance, the geometry errors reported by OSM Inspector.
- last, you can support the community growth by helping newbies. You can use OWL, OSM Mapper or one of Change monitoring tools to watch and help newcomers in the areas you wish.

Perhaps I am lucky in this regard, that I live in a large and (relatively) sparsely populated country, although even for me the places I travel through commonly are becoming well mapped.

For the local area there are always more details that can be added. In the city I am mapping cycle routes, bicycle parking, bicycle crossings. Some people are adding house numbers to all streets in the city.

From time to time a new road is built, or something changes. A new pedestrian bridge was built over a canal in my local area. I went down there on the opening day to get some survey data.

Outside the city, some areas have Bing imagery, and so there is tracing that can be done. For areas with no Bing imagery, I am constantly annoying my wife with wanting to take a different route when we travel so that we can pass through some town that is not mapped. :)

There is always plenty to do.

indeed, FWIW, being subscribed to this help in RSS, the question did interest me... LM_1 if your region indeed is exhaustively mapped you really are lucky --but check it carefully: that's what I thought myself here, and then I found that many little streets even in my own town, and far more in the villages around, are missing. And there is no harm keeping the OSM login just to update little streets from time to time ;-) Another thing you can do is improve the existing, either by adding street numbers, or all the good restaurants you know, etc. Hervé

This is an excellent question for a mailing list discussion. I suggest you post this question to the talk mailing list, or maybe even to talk-cz where there will be many people willing to share their personal stories with you.

This web site, help.openstreetmap.org, is mainly intended to find "the correct answer" to a question - not for discussion or brainstorming. See also the section titled "What kinds of questions should be avoided?" in the FAQ prominently linked in the top right corner of this page.

There are different levels of complete, here is one impressive example http://www.openstreetmap.org/?lat=52.213197&lon=-0.070408&zoom=18&layers=M Personally roads, foot paths, riverbanks wooded areas and landmark buildings are the subject of my preferred edits but I'm sure the map can always be improved.