I've been using a keyboard for over 20 years and I'm fortunate enough to not have any pain or RSI related issue. I've always used regular stock keyboards and whatever mouse felt comfortable to me (Logitech's G400 fits my hand like a glove).
This is even with many years of hardcore clicking and "worst case scenario" things when playing massive gaming sessions back in the day.
But, one thing I've always done from the beginning is to make sure my forearms are parallel to the floor. I always make sure my hands are well supported on the keyboard[0], and my elbows are well supported (on a chair's arm rest).
One thing that sucks about a standing desk (something I've been using for 2.5 years) is you lose that elbow support since your forearms tend to dangle.
[0] This doesn't necessarily mean resting them on the home keys. I don't know how to type properly and over the years developed my own crazy system. I'm pretty sure if anyone saw my typing, ergonomic is the last thing they would describe it as.
My main issue with standing desks (and most regular desks actually) is that I like to have the keyboard relatively low (forearms parallel or slightly downward) and the display at eye height (well, top row at eye height, maybe a bit higher); most screens don't go this high. Luckily most of my workplaces have had printers, and where there's printers there's the best monitor stands you can get: packs of A4 paper ;). Anyway I need a few more of those for a standing desk.
I'm not a fan of actually supporting elbows, that (for me) would lead me to leaning on them, which leads to 'hanging' and shoulder / neck issues.
When I had a sit down desk, I always tried to get desks with the keyboard pull out draw.
I also much prefer having the keyboard / mouse low, but then I just adjust my chair to also match that height so my forearms rest naturally.
Funny enough that's exactly what I used to prop up my monitors too. It's so good because you can fine tune the height by just removing a chunk of sheets.
If you sit up straight, the weight should be pretty evenly distributed. It felt like floating on air.
In the end I guess that's what matters. Try to find a set up that puts absolutely no strain on your forearms, wrists and hands.
You could create something similar with a pad of cheap industrial memory foam (can buy pre-cut on the web dirt cheap), double-sided tape, and some 68mm downpiping, but it wouldn't be adjustable to the same degree.
This is even with many years of hardcore clicking and "worst case scenario" things when playing massive gaming sessions back in the day.
But, one thing I've always done from the beginning is to make sure my forearms are parallel to the floor. I always make sure my hands are well supported on the keyboard[0], and my elbows are well supported (on a chair's arm rest).
One thing that sucks about a standing desk (something I've been using for 2.5 years) is you lose that elbow support since your forearms tend to dangle.
[0] This doesn't necessarily mean resting them on the home keys. I don't know how to type properly and over the years developed my own crazy system. I'm pretty sure if anyone saw my typing, ergonomic is the last thing they would describe it as.