I’d love to slacken my Humuhumu out and maybe change to a tapered headtube but I can’t afford to lose any toptube length, gaining some would even be good but then it starts to get simpler to just build a complete new frame.
I would actually probably wouldn't decrease the head angle. I am much more into twitchy steering tbh.
I could just build a new bike as well, but I like the chainstays on this and I have some spare tubes and TIG practice will do me good before starting full builds again. A warm up piece if you will.
Replace completely. Current one is 1".