can’t eject USB drives and others without using Disk utility command E (could not with 10.6.8 either - continued issues - expected a fix with upgrade)

The version of onyx that you have may not work with Lion. You can go to your utility folder and open it and then go to the top left and click on onyx. Then you should see an option to uninstall it, Since you don't use it that would be a good idea. When you created the new user,did you give it admin privileges. After you delete onyx, you could try out your usual user account and see if the problem is fixed. If not, and the user account you just created has admin privileges, you could transfer the userfiles from the old account to the new one. But, if you have any third party apps in the old account. You might want to add them one at a time and try out the eject external disk, to see if one of them is the problem. If you set the new user as admin. you should not have that much to transfer.

You can use disk utilities in the utilities folder to transfer to the new drive. Mount both drives and then open disk utilities and click once on one of the drives and then go to restore and follow the instructions. once you do this you will have to rename the original backup drive so that time machine will know what drive to use. You should erase partition and formate the new drive before you start.

I just figured it out. You need to trash your user finder.plist folder (Don't Empty) and restart. The OS will replace it with a new file. Confirm it is fixed and empty trash.