Like most Linux-based operating systems, the biggest challenge Leap faces is the GUI. I've found that while all of them are stable, there are glitches that occur from time to time, including lost functionality going from one version to the next. But these issues are more prevalent with the integrated options, and not the O/S itself.

End-users are more accustomed to point-and-click solutions they find on M/S-based operating systems. Linux requires a little more involvement than that, but I've found that SUSE has embraced the notion that similar functionality can be achieved in an 'X' environment as well. It just takes a little more effort to get there. 

"Major" mass adoption may not occur until third-party application providers design their applications to run in an 'X' environment, and not just for Windows. This will be dependent on them, as they determine market demand and whether there is any real return. There are those who have provided powerful tools and application suites, such as The Document Foundation's LibreOffice, that are very competitive, and are opening the eyes of regular consumers, which will help in spreading awareness. Time will tell, but I look forward to what the future brings.

The initial system setup or network configuration of the solution is not straightforward and can be improved. You have to go forward and back with several screens in the setup tool.

I have issues configuring my video card because the solution is open-source and there is a lack of information on how to configure the video card properly. There is room for improvement in the documentation.

I would like openSUSE Leap to have better link integration with Windows.

In the future, the Active Directory could improve.

There is room for improvement in the console. 

In additional features, I would like to see more automation and integration with popular community-developed applications.

Somehow the change from OS12.x via 13.x to Leap was a bit bumpy and some old issues seemed to reappear. This would not affect a user that chooses this distribution from a fresh start.