My DD prefers the sleeveless with a Dri-fit or Warm Gear underneath. She is a pitcher and says the sleeveless are more comfortable. She also hates long pants. She rolls them up and holds them with a rubber band and socks.
DD's team (16U) has 3 tops, racerback, with the digital camo, a traditional button up short sleeve, and they just got a short sleeve dry-fit this fall. She likes the dry-fit the best. then the racerback. As a catcher she hates the long pants, so won't even consider wearing them. We did see a lot of teams this fall with the long pants and I thought they looked ok. Looking and playing are two very different things though.
I told my DD about this thread last night and she exclaimed - "OH MY GOSH THOSE PANTS MOM! tell them don't get the pants!!!"
I wonder if ours were poorly made and had a worse fit than typical because she is slender and not hard to fit. But she also wore them rolled up to have less pull at the knee/hips when pitching.
Uniforms are the number 1 waste of money on any team, IMO. Get 3 or 4 different colored dri fit type material jersey and the same in bottoms(pants or shorts). Have 4 4 complete uniforms for around $200-250. It was cool to get the nice uniforms when they were young but with turnover and teams coming and going it just didn't make much sense to have $60-80 vested in one uniform.
Second year 16U team here. My girls want nothing but the racerback shirts. They say they are less restrictive and much cooler although with the new materials available, I might question that. The pants they really don't care about but they are thinking strongly about requesting to go to the long pants. DD is a catcher and has played in both. She really has no preference other than to say that if we're going with the sleeveless shirts, they would look kind of dumb with the long pants. Our pitchers on the other hand, may have something to say about them. I can get them for the same price so it really doesn't matter which way they want to go.
We went with 2 different Dri-fit shirts this fall when we started the team up, thinking that in the spring we would get a 'nicer' button down jersey. Most of my girls and the parents don't want us to do anything other than the Dri-fits now.
I don't know about trends, but I prefer the short sleeves. It never seems to fail that you miss one spot around the arm and wind up with a painful sunburn in one spot. My biggest pet peave is ankle length pants in softball. It looks wrong to me-especially win worn with a sleeveless top.