I think they are all pretty but am partial to the small ones that have prevalent for the last ten years or so. My neighbor has little round colored lights on an outside tree. I've never seen them before and they really look like bubble gum from a machine. They are very pretty. I probably don't know what you are talking about LED lights for Christmas. I haven't decorated for Christmas in quite a few years. I thought I might this year but not doing it again. I have a nativity I always have out at Christmas though.
On my prelit tree ...small bulbs. Outside we have the projector lights. Just plug it in and it shoots the moving lights on to the house. (Not the Star Shower but a different one that is multiple colored) And another one that shoots stars that rotate on the house. Very easy---nobody has to climb the ladder and hang the lights.
Small non-LEDs are my preference for the tree, C9s for outside. I hate LED Christmas lights. They aren't warm, for one thing. The blues and greens are always much much brighter than the reds and yellows and thus when you see a house with LED lights, it looks icy cold and ark with blue light standing out the most. LEDs also give off no light; there's no "warm glow" that the incandescent ones have. At our we house, we use all incandescent :) Screw the energy bill ;)