Do test coating 1/1,1/2,2/1,2/2 etc and then expose a design that will allow you to test different parts of your screen for proper eom.
Go with the coating technique that proves the best for you.
When I used the PHU I coated my 150s 2/1 with a monster max scoop coater and everything higher 1/1.
Generally, doesn't one need more strokes to coat higher mesh counts since the mesh naturally holds less?
With thinner emulsions yes. That has been my experience.
Both the PHU and the T9 are thicker bodied. So if I tried to go 2/1 I would be printing HD sim process