Del-I’ve had XT, XTR and LX, juicy 7’s etc even Hope Mini’s.
I do like Avid’s pad adjust on their top end.
Once a Shimano brake is setup properly-it’s awesome.
My XTR is 160mm and the modulation is great.
I’m 92kg-not fat you cheeky fecker Dibbs ;O) but have to agree go for the 180mm with metal pads.
With the servo lever, 180mm rotor you’ll stop really well and also resist heat for a bit a longer.
If you are going rigid fork-then deffo 180mm on the front, 160mm on the back.
My XTR seemed on par but the power on a 180mm LX was great.
Shimano are vast-parts availbale even from Halfrauds and easy to sell or use on a commuter/new build.
Just watch the aluminum threads.