Thanks to all who've been replied. Your comments are greatly appreciated.
@Tobin

I get what your saying about rubato and the difficulties involved in a time based grid system.

And yet BIAB does actually have a New Age midi style that's described as rubato, AWAKEN2

I've tried with limited success to make useable rubato jazz styles but with one or two exceptions the ballads sound better with tempo 'arcs' applied to the song; gradually accelerating to a peak then decelerating over various phrase lengths. You need to work with them otherwise they drift or sound clunky.
As well as the right patterns, track slides/offsets can also help greatly in achieving the right 'feel'

Yet rubato is maybe something that would flow better with real tracks. I don't know.

I'll try to post more up-to-date youtube videos of jazz from the 90's onwards.
There seems to a lot less 'swing' as such nowadays and what there is harkens back to the original post bop/free bop sources.
Complex straight eighth patterns predominate but don't necessarily resolve in a couple of bar lengths like so many midi style tend to do.
Whether real tracks or midi, swing or straight eights, the gold standard should be the METH80/81 style where the drums are carefully programmed over 8 bar phrase lengths. That style one of the most successful and propulsive drum grooves ever created in midi.

Above all when I think of modern creative jazz I think of intensity, drama, variety of gesture, a sense of interaction between front line and back line that blurs the boundaries between the two.
It's the polar opposite of a low intensity background music stuck in some sort of 50's lounge bar time warp.