Gentoo could really use a faster package manager too, that also hopefully has less package conflict problems. Also, a good way to deal with proprietary software that has library conflicts, like Steam. These have been really big issues for me lately, and I've been spending a lot of time updating everything with emerge.

I think more of the general public should learn to use command lines to a degree. because command lines are very good user interfaces for many things, but I don't think the public should be introduced to Linux and needing to use them. Rather, I think Linux distributions should have powerful graphical tools that users can use when they first switch, then they can optionally learn about the command line when it is more convenient to do so.