I agree with getting the LED
units. If your bulbs are the original ones, you're due to change them before you get any new corals (other than polyps perhaps). There is the price of one of the LED
units right there.
As for water clarity, I don't think a skimmer will make any difference, as that's not what they do. A filter sock on your drain pipe will help, as will chaeto in your sump if you don't already have some. Of course a better skimmer will help with any nitrate issues you may have.