Okay, well I've got 2 'calibration' prints i use.

Both useful to keep and great to give away.
And I will say that a printer needs to be dialled in well to produce both.

So the first is this phone/tablet stand.
It's 2mm thick, has (takes one out of pocket to count) 6 print in place hinges. Fits a normnal wallet and will hold up to a ipad pro (biggest I've tried).
https://www.thingiverse.com/thing:3334689

I'm pretty sure I've printed one at 100mm/s on the twotrees sapphire pro2. But 75 gives a better result.

My other calibratuion print would be this iris box: https://www.thingiverse.com/thing:1817180
I have printed these at up to 150mm/s
But I did cheat on my delta :-) and used -0.1 mm for internal compensation.

On the sapphire pro I used 0.85 extrusion ratio.
Useful for items with a lot of close together nested layers.

I also use simplify3d as my default slicer.

Standard pla settings:
200c
65c bed
3 walls, 3 top and bottom layers and 15% triangular infill.