I can recommend a small split ortholinear keyboard. I built one as a weekend project and it was pretty fun, doable with basic microcontroller and solder skills (except for the ~50 SMD LEDs which I couldn’t be bothered to do). Pretty happy with it, it’s comfortable and I do feel that I type better than on a regular keyboard. You can buy kits containing everything you need, I got this one:
https://mechboards.co.uk/shop/kits/helidox-corne-kit/#case
With small keyboards, you’re trading off physical distance between keys for having to press more buttons simultaneously. Might fix your problems with reaching key combinations, but the combinations themselves do become more complicated as well.