but I never mentioned casualties but ground taken which is much more an objective measure
where has regime change led to a better outcome ...I'd say Iraq if that is recent enough , big improvement on Sadam IMO and no longer aiming to kill their own people (you'll notice the US got out and have no influence in the country ) but yes , very good chance whoever replaced putin would be more of the same ....possibility of improvement only (even a bad leader would still stop the war though as it is no longer is in russias interest or winnable IMO- simply blame putin and cut losses)
nuclear blackmail cannot be allowed to succeed either or it will be repeated little chance of Armageddon here but more chance of a tactical nuke being used taking a less risky path can be more risky longer term
russia I believe will be forced back inside it's borders and hopefully end this expansionist phase once and for all the bargaining point may be crimea - slightly different situation - a proper vote would be fairest