I wouldn't call it a big regret or anything but I do wish every so often I had any knack at all for drawing/designing clothes. Because none of my humanoid OCs are Normal™ about what they'd wear– this is part of the fun– but I personally myself am at the "stick figure on a napkin" tier of artistic skill in this discipline. Making clothes in real life is more accessible to me than desingning them! And I'm not especially talented in that regard!
"Why not learn? The internet must be full of info!" No, I am the tier below that. I know so little that I have no appreciation of what I don't know, which means finding the matierals to teach me would be straight luck. And I don't seem to have a knack so I probably wouldn't pick it up very fast and ughghghghghgh if I'm going to contemplate stretch-hobbies I'll never get around to I'll think about archery, ok?
But it would be cool if I could do it. That would be neat.