In the original game, you used to be able to press Page Up or Page Down to pan a little above or below Bob's location to see if you were missing any items. This would be a nice addition since the length of time Bob can stay under water seems to have gotten less and it's almost impossible to reach some items that are under water.
I agree that this would be helpful, but I would like to note that hitting the tab key brings up a map of Bob's surroundings, which also serves well for spotting those elusive items.
I am aware of the map. :-) However, I found the panning feature that used to be available more helpful.