After using Gnome Shell for a while, here's some things I think would make it better than it already is.
There's need for a more convenient way to clear the trash. Right now, I need to open up Nautilus just to be able to right click and empty the trash. A trash icon on the launcher would help. It seems I'm not allowed to create on of my own.
More advanced users would likely appreciate keyboard shortcuts for launching apps on the launcher (like we can with Unity). It's much faster when you have a few apps that you frequently open up. Gnome Shell doesn't seem to have this facility right now, or it's not very discoverable if it has.
Alternative system menu by default
By default, Gnome Shell's menu only has suspend. We need to install the alternative menu extension to get the power off option out, or we could Alt-click on suspend (not very discoverable to newcomers). It'd be nice to have this "alternative" menu as the default instead, or at least provide an option to show it in the default Gnome Shell setup.
Better clock applet
Gnome Shell only shows time by default. You need to click on the clock applet to view today's date. It'd be a nice option to be able to show the date and time together so the user can check the current date at a glance. This is like the alternative menu: there's an extension to get what I want, but it'd be awesome if Gnome Shell came with it.
If anybody's been reading this blog, they'll know I've been posting boot times everyday recently. With Unity my system gets a boot time that's sub-minute. Gnome Shell exceeds a minute (just a little). If it's the old Gnome desktop, I'd just put it down to old architecture/design limitations, but Gnome Shell's a modern desktop built for the future and only came out not too long ago. It needs to be much more nimble than it is right now.
So there you have it. Did I miss anything?