You are making it hard by trying to figure out what that perfect for you stem length and rise is before you get one. So instead just get one and try it. If you like what it does for you, then it matters not what any of us think. If you don't like the results then you can try something else.
Also understand that a lot of what you read are by and for people that ride their bikes in very demanding conditions. If you just ride your bike, then those things they are talking about probably won't amount to much for you.
I wouldn't get too concerned about cast or forged. Just try to get a stem from some manufacturer that is reputable and has made stems for a long time.
If you change your stem length to shorter, then it might make the bike seem more twitchy, but you'll get use to it after a few rides. I changed my stem length from 100 to 70 millimeters a while back and that twitchy feeling wasn't really anything more than just being different. If the bike had come with a 70 mm stem from the start, I wouldn't have known any different.
Last edited by Iride01; 10-18-22 at 11:40 AM.