Here's what I'd do with a wild (i.e. not to a metronome) recording like this:
- Beat Map roughly, like once every one or two bars, like I did with your file, so Logic knows how I meant what I played. This will create a Tempo Map which follows roughly what I played, leaving my little wanted or unwanted fluctuations between the mapped points. This leaves the human element in and avoids the mechanical rigidity that comes with hard quantisation.
- after Beat Mapping, select the Region, ctrl-click it and select Tempo>Write Project Tempo To Audio File.
- engage Flex in 1, 2 and 3
- now I can change the Tempo Map to lessen or remove unwanted fluctuations on a macro level or to change the tempo of the song entirely, and the Region will follow. However, my personal inaccuracies on single notes or phrases still remain intact.
- Once I found a good tempo structure, I may (or not) try to refine my less-than-optimal playing skills either selectively with Flex Markers, or globally by using gradual quantisation, either on the entire Region or I may further divide the Region into sections which require more attention.
I'd much prefer this approach to simply manually Flexing every note to a static tempo, because a) it's much quicker, b) it gives a much more natural feel and c) it is much easier to change later.