blur/sense/touchwiz all suck badly there are many 3rd party launchers i.e launcher pro,adw,ahome etc.
my personally favorite if your looking for a more vanilla look is launcher pro plus.
launcher pro is free and is full useful in the free version but you have the option for i think 1.99 to unlock the plus version to use some built in widgets and to be able to resize widgets.
unless you live very far from the store i recommend buying the atrix and tweaking it for a few days as most stores install task managers(horrible!) and these do more harm them good whenever i stop in a local vzw or att store to play with a device or two while the wife is shopping they lag horribly and 9 out of 10 times advanced task killer is running and the devices stay on for days. if you dont like it then you can always return it.
I say try and use the device to its fullest before looking to root then once you hit the wall with something you want it to do then look into rooting.
since the atrix is on at&t i recommend the android central sideload wonder machine as att does not allow you to install non market apps.