I was just very surprised after opening the app that the UI looks very different. I think it's great that lucky clan always tries to improve their UI, however I see two major issues with this new design, that I think should be adjusted quickly.
The first one is that the new background color in darkmode is too bright grey now. It should be darker than the rest of the UI (as before), not brighter. I personally think this new lighter grey background gives the app an outdated look, and is distracting while painting. It doesn’t even feel like true darkmode anymore. Any other painting app on the market has the standard of dark grey background, lighter toolbar, because it’s better against different colors, and more neutral/ modern overall.
Also the new side sliders are a bit distracting because, there is a lot of "white space" in them, which distracts the eye in the peripheral because it’s too much/ too high of contrast for darkmode. It also looks a bit out of place, since it doesn't fit the overall selected color scheme anymore. If you're keeping this new slider, I think a thinner "white space" slider similar to Procreates implementation should be considered. The thinner slider could also match the color scheme (not necessarily). I attached a screenshot to roughly explain it all.