I have never, ever been forced to reflash my tablets because of installing or uninstalling an app from maemo.org. Not once.

It sounds like your tablet might have hardware or other problems if you're forced to reflash, especially if it's happening so often. You might want to consider getting a repair or replacement under the guarantee.

If you want to troubleshoot this, perhaps you should give some specific examples of apps you've had problems with rather than saying "just about any". We could then try installing them and compare what happens.