Not a bad idea I suppose, but not really something high-priority.
It's really only a cfg file that holds the account info, so you don't need two users.
Anyway, here are a couple temporary solutions if you really find it to be too annoying. (I haven't tested either of these, btw, but I don't see why they wouldn't work.)
1. Copy the osu! game folder and create a shortcut for the separate accounts.
Only issue with this is wasted HDD space and separate song folders, etc.
2. In the osu! game folder all the settings and account info are stored in a file named something like (osu!.user.cfg)
You can copy that file for one account, log into the other account, change settings and then copy it again to somewhere else. You can then just replace that file with the config file for your account whenever you're going to play. This whole process would take less than 10 seconds once you actually have it set up. If you're familiar with batch files, then it could do the whole process in less than a second, but that's out of topic.
Hope it works out for you ;d
