Unless it's quite cold out, I find that I can't walk in rain chaps or rain pants of any sort without getting wet from the inside-out. If the weather isn't too cold to make it practical, the best approach I find is shorts and poncho.
When it is cold enough to sustain some sort of rain pant, chaps are great IMO, particularly due to the ability to more easily put them on and take them off ... one leg at a time. Less nice sometimes in camp or at breaks as you can't sit on anything wet without having something (else) dry to sit on.
Most of the time when I carry chaps, that's exactly what I do ... carry chaps, not wear them.
Since I use a poncho, I'm not interested in a rain skirt, because a loosely belted poncho is basically a rain jacket plus a rain skirt anyway. If poncho is long enough, one could consider relatively long & light gaiters instead or --- just let the lower leg get wet. The only issue with this latter strategy is if you're using some sort of waterproof or water resistant shoe, you don't want socks to wet out from the top-down.
One suggestion before buying rain chaps is to consider making a pair by converting frogg togg or dri-ducks pants (when you buy a set of these they come with both jacket and rain pants). My converted dri-ducks pants work great as chaps, were inexpensive given that I also got a jacket out of the deal, and it wasn't a great deal of sewing work to do the conversion.