What awaits you with scuba diving is a further loss of $$$.
Then again, I'll probably be more appreciative whenever I actually get the plate for my mask (prescription plate so I can see). And one of those nice wetsuits instead of the rentals. And my own BC.
Maybe even a tank or two, someday.
I don't have a huge grasp on saltwater aquarium fish yet, but one of my favorite oceangoers is the giant Pacific manta ray. Has to be the most beautiful fish I've ever seen.
I also think oarfish are pretty wild. :P