A second 'me too' for the desk mat
And a resounding yes to hotswap switches. I went a bit mad for keyboards this year... I have a Drop Alt, Ergodox EZ and Preonic. I also now have a container full of different switches and keycaps.
What i have come to know is that i like Ortholinear keyboards (a lot), tactile ('brown') switches, and that I would be very unlikely to buy a keyboard that doesn't support QMK in future. I very much like high profile sculpted keys too (SA profile, if you are interested). I'm not a fan of expensive keycaps, people seem to spend crazy amounts, just to have pretty colours (each to their own though, the aesthetic doesn't really matter to me, but if it does to others, that is fair enough).
QMK: The ability to make the keys do exactly what you want them to do is pretty cool once you get used to it, some examples:
I can hold down j or f and they act as shift keys,
I double tap y to turn caps lock on/off - I had never liked caps lock before, but set like this it is quite nice
If I hold my spacebar down it acts like control for useful keys
I have a bunch of keys that send odd key combinations, Karabiner, autohotkey or autokey (mac, win, linux), trigger macros / events from these. My media keys control a sonos system rather than a media player on my computer is one example.
Some simple combinations output text I regularly use ('| grep -i' for example)
Then there is customising lighting, which can be quite useful
Just learning to do more with fewer keys, which is a mental strain as you get used to it - initially I found it to be tiring getting used to how my keyboards are configured, over-coming literally decades of muscle memory, but once familiar it becomes fairly clear how inefficient 'normal' keyboards and keyboard layouts are (the biggest key is
normally the space bar, and it's really useful, but having it only do one thing is a massive waste of space).
Hotswap: beyond just liking that I can fairly easily try different types of switch, I like having different switches for different areas of my keyboard: my escape key is a fair heavier switch than the rest of the board, arrow cluster is a lot lighter, modifiers feel different to letters.
I had a fairly cheap hotswap non-qmk board previously, and the keys I don't like (caps lock, scroll lock, insert), had heavy clicky switches, I
really knew if I hit one by accident!
Ortholinear keyboards are grid layout (or offset columns rather than offset rows), which again take a fair bit of time to get used to. Personally I find them a lot nicer to type on. I would definitely say that whilst I much prefer this type of keyboard, it is the one area of the three (hotswap, qmk, ortho), that I would not say is necessarily a universal positive. My partner just can't type on an ortho keyboard, no matter how much she practices, and she detests them.
I am still a faster typist on a 'normal' keyboard, but I am a 'better' typist on an ortho and it feels nicer as a layout, to me. I think it will be at least another six months before my typing speed matches, but I tend to have better habits on this layout and I think I will end up being both faster and better. (not that I am a slow enough typist that it is actually a problem anyway).
So yeah, hotswap switches and qmk, lovely things to have on a keyboard. I'd generally look for them in that order on a keyboard. Ortho, worth trying if you can either get a cheap one, or borrow one for six months, it is frustrating at first, and may not suit many (or even most) people. And trying different profiles of keycap to find a type that suits you. Aliexpress can make a lot of experimentation, well, not cheap, but not hugely expensive either.
