May's deal or a.n.other most popular Leave option versus Remain. Binding so that Parliament must go with whatever wins. UK elections for the parliament could be deferred until the second vote and wouldn't be needed if Leave won.
For a political genius these are some weak sauce arguments
Nice try but you're weakly arguing from a UK point of view.
European view is they want it done as they need to move on. Not prepared to change their election laws to accommodate something that isn't even guaranteed. Would almost certainly be vetoed by a number of EU states. They aren't going to leave their Parliament in limbo whilst waiting for the outcome. UK seats already been reallocated for may elections. Would again be a legal challenge from within Europe from any number of sides which wouldn't be resolved quickly and so you'd have a lame duck Parliament. There's too many seats at stake with how close the predicted voting blocks are going to be.
You've got 3 options so if Remain gets 40% and the other 2 leave get 30% what do you propose? Surely can't be remain if the total leave vote is 60%.
More leave options you put up the greater the chance of them being chosen as people start cherry picking again.
Another popular leave deal isn't even on the European table as it hasn't even been negotiated yet.
Highly unlikely Parliament is going to pass a bill even trying to make a referendum legally binding as goes directly against the precedent of Parliamentary sovereignty.