Just thinkin’ aloud.
But as you say, it's the one we've been asked. Fuck knows why anyone would think a referendum was a good idea to decide anything important, but there we are.
My own take on where we are now, fwiw, is that the EU have played it straight, despite the last minute cock-waving of Spain over Gibraltar and Macron's fishy threats, whereas our "negotiating team" has been led by a lazy idiot who showed arrogance and contempt for well over a year of doing nothing, before bailing out once he realised he had no idea what he was doing. Followed by another one who basically also did nothing as May had taken over by then in truth.
To be fair to May, the deal is probably not a bad effort in damage limitation, given that it was obvious to all but the ideologically blinded right from the off that no negotiated deal would be as good as staying in the EU.
Much as I dislike the idea of "going back to the country" to ask The People again, it does seem that the only sensible way to determine the way forward now is a second vote on either staying in, taking the deal, or leaving with no deal. Although if that last option was to be included it would need some more fleshing out otherwise there will be those that can paint it to the gullible as an attractive option (knowing damn well that only the Moggish disaster capitalists would actually stand to gain from it).
The reality is that two and half years on, we still haven't had a single coherent answer to the question of how we will be better off or what the advantages are if we leave, other than May's latest rhetoric reinstating the queue-jumping foreigners as the main evil to be "ended once and for all".