Yep, optimisation was a big goal. I'm testing this new version a lot at the moment, and checking the difference between high detail particles on and off. that being said, this is a mod designed to immerse and create a more realistic experience. During the Napoleonic Wars, there would be smoke much thicker, and longer lasting than I have added.
The High Detail button can be flicked on and off at any time however, so if you need more vision or more frames, just hit the switch