Hi Metin, yeah I think it has helped a lot to have the worst old Windows XP style icons replaced. And the new font helps improve text legibility. The text difference is especially pronounced for the Mac version where it's now drawn using the native Core Text functions instead of with FreeType by way of Wine. There are numerous details improved for the Mac version so it won't be quite so weird anymore, things like full screen mode working normally, window sizing from any edge instead of the old fashioned corner only, should support Retina properly now, should work fine with multiple monitors with default OS settings, and others... It will still be a little bit weird since it's a cross platform app that has it's own style conventions and doesn't follow any one single operating system's style conventions exactly, but it won't be "unnecessarily" weird anymore. Also it should not be so susceptible to getting broken by new macOS releases either, at least I fervently hope so!

re:
> what will be the most significant changes from MoI V3 to MoI V4?

I won't know the complete list until much further on in the beta release process. The only things I can promise for sure is the stuff I've been working on so far which is 64-bit (for both Windows and Mac) and the native Mac build. I am really looking forward to working on new features though instead of porting and rewriting. Filleting improvements are not looking likely for v4 unfortunately. Grouping, instancing and basic dimension functions are probably the highest things on my radar right now.

- Michael