Work around tips:
Bookmark your search results.
Highlighting variables, temporarily rename them "IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII" and you can spot them in the events easy.
Navigating, I find the spacebar & mousing the fastest. (I'm a big photoshop user)
I know a lot of the problems with these were C2's GUI, which is what brought about C3, so I understand it may not be worth fighting C2's. That being said, based on my workarounds...
New thought on "highlighting" backend, it may be easier to implement adding the flag to the name. Rename the variable with non-typeable character on the end when the user checks the box on that variable. Would save extra coding, just highlight everything with that character.
I picture people keeping 90% of the variables highlighted all the time.
Thinking back to old search posts, I think a lot of them were before the bookmark code was added. That would be a good solution, a second bookmark bar for search results. All search results get bookmarked there, and that bar opens. You could put a button in it to hide all non-bookmarked events, so people could still have the old look. (Arima) Actually, that might be a cool feature to have in the regular bookmark bar as well. (plus it adds to interface consistency, less to learn, blah blah)
I'm picturing un-marking irrelevant results and keeping the results around awhile.
The Navigation thing is "If scrolling" and the cursor hits the edge of the screen, subtract (or add) the screen width (or height) to the cursor location. E-on's Vue does this, you keep moving the mouse and the cursor will make several trips up the screen.