For future reference, there are a few pointers that might help.
As you found out, it is best to batch import the online material after you have finished editing with the offline material and do not need it anymore. It helps reduce the clutter. In newer verions of AVID, I think it is standard across the board to be able to relink to a select online resolution though which may help keep it all separated.
I think you may have had offline bad media still online because you either imported them into a separate bin, or possibly in multiple projects project. I find it is always a good idea to try to create a separate project just for graphics, and another for music etc. This helps you keep things organised later on when you are trying to delete material int the Media Tool. You can always use Media Tool and Select Media Relatives to fins out what material your sequence uses and and be selective in your media control.
You don’t have to copy paste ad nauseum in AVID for tape ID. You can create a tape for one item (whether it be graphics, music, etc.). Then highlight all the clips you want to change and use the Modify Clip command and set source, then seelcting your proper TAPE ID. This would have saved you the 142 keystrokes. The inability to use puncuation is so it won’t screw up EDL’s and it best to avoid lengthy or punctuated TAPE ID’s anyway.
For graphics, three things to remember if you are doing rough offlines and then online finals is it helps to keep the exact names of each set intact and the same (even if they originate from different folders on your computer, import them with the same duration and give them a pseudo Tape ID like “GRFX001”. If you do this, you can then organise the offline graphics, delete the rough stuff (media only) and then use the [i]Relink Command[/i] which will look for the same tape, duration. etc. and relink your previous offline material clips to the proper online grfx media all in one go.