Strongly dislike any kind of lined leathers for changing length… it seems like they all buckle at least a little bit when they bend on the holes you regularly use, and then over time it becomes impossible to pull that bit through, regardless of how thin they started out. I usually have an easier time with solid single ply non-stitched leathers, even if they’re thicker. My stirrups on my saddle have stupidly thick old leathers (literally over 20 years old) but the only way you can tell which holes I use is because the color has changed. The entire length slides easily through everything, just because it’s so evenly smooth. (And yes, I inspect them regularly for wear, because–holy cow, 20 year old leathers. They just don’t make them like that any more.)
I do want to order a pair that have the T-bar adjustment system sometime to see how they suit me, they are supposed to be the easiest to adjust (and not dependent on stirrup bar area), but it seems 50/50 love/hate for them online.
Re: Color. You can always keep your current leathers for shows, if they’re a nice matching color. Generally plenty of time at shows to dismount and fidget with your stirrups as necessary in between classes.
(Side note: I am lucky not to be one of the types who is bothered by a big lump where the buckle is. I have my own princess&pea crosses to bear, though.)