Thanks, everyone, for sharing your opinions. I'm very grateful that you did that. A special thanks to Angie for the one hundred thumbs up! I din't expect that, but highly appreciate it. It seems that the majority prefer the blouse as it is. My personal opinion is that a minor shortening of the sleeves would be a good idea for a start. I also think Ramya has a valid argument that this easily can become a new wardrobe orphan, because it is an outlier. However, at such a low cost, I don't consider this a big risk, but rather an opportunity to stretch a little.
The blouse will stay for now, and if I'm not wearing it, the sleeves might get chopped off later. That's in fact one of the things I really like about thrifting: Unusual pieces that I can play around with at a very low cost. When I'm done with them, they just go back again, no harm done at all.