Having now looked at the way people are using tags on wists, it seems like the most useful way to avoid tag overload is to bundle tags into search so that search is the gateway to both full text search and tags i.e. tags are a way of narrowing down structured searches.
This means that we can probably drastically simplify the Wists interface.
Currently working on full layout control via the url so that you can create cut and paste javascript code to place Wists galleries on your site, rather like Flickr’s badges. More details on the wistsblog.