The get-lane installation could be fixed up a bit to better handle mysql permissions. Right now, if you agree to install the sample data, but then provide incorrect credentials to mysql, the script just continues. It should probably reprompt for a user name and password that works, or use the root credentials provided earlier in the script.
I've been thinking about writing a graphical installer, in Python. It think there's a number of problems in our current installation related to the point you are bringing up here. I almost started working on it last night, but after finishing my hours up at the coop I was pretty well spent.
Maybe if I can get the kids to bed on time tonight ...
I did do some starting work with learning PyGTK, and building some interfaces, but nothing concrete towards a graphical installer. As soon as I have some initial work worth sharing, I'll upload it to my fork of the application.