Current Sea Dweller owners - what would make you switch?

[WAK4]

So with all the chatter of the SD4k possibly on its way out, I was wondering if a new 50th anniversary model is released to replace it:

1) what would make a current owner switch to a new version?
2) what could entice you to own both?

I've said all along I love mine as is, it's the "if I can only have one watch" watch. Some red lettering would be awesome, but too little too late for me as I'd probably just stick with what I have vs bearing the cost to change up. If coming in as a new owner, then I'd probably want that red lettering.

Bigger case? Green gradient dial (a la Deep Blue...)? Deep Sea type clasp?