Er, which illegal aliens ? Are these a substantial fraction of the Kosovo Albanians ? It does not seem that they are.
And how would this change the politics of Kosovo ? Even if you found some magical non-messy way of wishing away every “illegal alien” there would still be an Albanian majority that hates Serbs. And would the non-illegals count as “moderate Muslims” ? If not, whats the point of distinguishing them from the “illegal aliens” ?
And what would you need to conduct an examination of legal residence and expulsion ? Nothing short of another period of Serbian domination I think, with attendant warfare and suffering all around. Is that issue of illegal aliens so important as to justify that ? How would you justify it to a third party that does not have a mystical Serbian attachment to Kosovo ?
Which criminals ? Serbian ones too ?
There are hundreds of investigations of war crimes of all kinds going on in the Balkans. One of these days the odds are you will see a bunch concerning Kosovars (on both sides). Thats cold comfort after the fact. More important is to keep people from killing each other.
And that does not address your point about “moderate Muslims” in any case other than Kosovo, if that - if you are holding on to your point, you have to address ALL the implications of this.
You must know history..when there is a strong Serbian state, there is peace. When there is a Serbian state being weakened and torn apart from outside influances, there is conflict in the Balkans. The Croatians were a counterbalance to them = peace.