The support thing can cause issues if you are using another material, especially on single nozzle machines as the filament cools between layers, maybe if I had a tool changer or nozzle swapper it might be easier, but for a single nozzle machine that takes a minute to change and purge filaments I'm deffo going to be looking at printing whatever I can without supports, might mean a slight change in the plan for what gets printed in what, but shouldn't be too much of an issue, will just have to look at the different parts of the model I am printing and decide from there...
when I need supports, I only use support interface material now because the finish is just so damn good. I don't disagree that it could cause issues with layer time and layer cooling between changes but I think it's such a small thing it's almost a non-issue for most filaments, especially if you have a chamber and the overall print environment is stable