Clipless can make a huge difference over platforms...but it does take some practice to get the most out of your pedal stroke.

My former commute was 12 miles of constant headwinds on the ride home where if you stopped pedaling you pretty much stopped moving. It took me a little while but I eventually learned to apply power over the whole pedal stroke with both legs and keep myself tucked tight (for wind drag). The difference was huuuuuuge.

If you go the clipless route, I'd recommend practicing on them before taking them on your commute. Ride around your neighborhood (or similar area with very few cars) and practice clipping in and clipping out.