The update is purely cosmetic, so you wont miss any stakes at all.
Not too many changes in source files, so what is that huge difference from?
Two reasons I can think of: HQ icons and building with Qt5 instead of Qt4.
Well, actually the total size of files in 2.0.0.2 is ~4 MB less than in 2.0.0.1; splash3.png is now 1 MB less than previous version, and few PNGs were removed, so the new version should be rather smaller. So, you think Qt5 was used and it added 15 MB for keeping some air in the EXE :-) ?
You're welcome to build a release edition yourself with Qt 5.7.0 and have a look.
Edit: just checked and v2.0.0.1 was build with Qt 5.3.2. Don't know why my version is bigger. I will have a look at it!
Just tried building in a linux environment using MXE and I was able to cut the .exe down by 1MB, but nowhere near 9MB the previous version was at.
I'm not sure what happened there. I will look further into it. Thanks for bringing it to my attention.