I can only speak for myself of course, but that wouldn't be my position. Ideally, for me, these negotiations would lead to the following outcome:
1. A tough but fair deal that will undeniably leave the UK in position that is measurably inferior to their previous position inside the EU.
It's clear that a point must be made: leaving the EU was a mistake, and that fact needs to be felt. So far this point has actually been illuminated quite well, in part due to the UK's complete unpreparedness to deal with an actual Brexit, but it has to be clear for the longer term as well. That way the rhetoric of "short term loss, long term gain" can die off.
2. Avoid the feeling that the UK is being spited, or punished.
The United Kingdom is still a good friend and close ally, and the deal should reflect this. Measures taken should not go further than those resulting directly from loss of EU membership, in fact, some of these should be mitigated. We are not spiteful, and we respect democratic decisions made by our close friends.
3. The door to return stays open, but this should not be repeated too often or too early.
So far Macron and some others have made this point, but I actually don't feel this point should be hammered upon. It is good to remind UK citizens, especially those that wished to remain that we don't turn our backs on them and that the cause of UK membership is not dead, however overstating the fact can have the opposite effect. It may even come to sound desperate which doesn't accurately reflect that the EU without the UK among its members will be just fine, and that the UK even without EU membership will be too, even if it means they end up somewhat poorer.
All these factors together should contribute to the following goal: That a large majority of UK as well as other EU citizens consider the brexit in the future, and think "Why the hell did that happen, all it did was cause a mess and make the UK a little poorer."
I think we are well on track.