Photoshop would just about be OK at 200% but the LNP toolbar works out to 3.5mm x 52mm (0.138' x 2.06'). A poster was asking about a 15' Alienware laptop with a 4K screen in a recent thread.
I'm thinking that is going to be a real problem on a very high resolution screen. The UI has the same font size as the main LNP panel, and I don't know any way to change it. The toolbar floats on top the same as the main LNP panel, but it is a bugger to pick up and move, and I still have not got that off pat. It turns out that a toolbar was added at the end of May this year and can be turned on from the File menu. You can add shortcuts for your favourite presets, at least one of which Guillaume fixed specifically for me (he is incredibly helpful) but with more than 40 presets, all of which are configurable, you can see the problem. The UI has become more complex over the years, and a preset that you use only occasionally, becomes a chore to find.
While LNP is far and away my favourite Photoshop plugin, the ever continuing addition of new features and presets leaves you with a 'can't find the wood for the trees situation. While discussing my Lazy Nezumi Pro appearing to make Photoshop freeze issue with Guillaume Stordeur - the author of LNP - he asked in passing, how I was getting on with the new toolbar