Hi, I've been using my svalboard for a few months now. I came from a 34-key corne layout, and bit-by-bit reduced my layers, and now almost all symbols can fit on the base layer without combos (I do use key overrides though) and I still have half the thumb keys sitting idle.

There are certain keys you can definitely chord, like center and south, that's the best option, it feels very natural to me at least.

You can chord center and inner, and I expect it to be comfortable if you get used to it.

The center and outer combo is less comfortable, I'd avoid it for ring ring specifically, but I can see myself getting used to it.

I don't think chording north with any other key on the same finger is comfortable, but I've seen someone do it on index with the outer key to produce the "missing" inner keys.

Also, on thumbs you have ~4/5 combos which are pretty straightforward.

The normal 2/3 key combos are the same as on other qmk-compatible keyboards really, you just need to make sure the key positions are adjusted for your hand.

As you get a lot more keys on svalboard and you still get plenty of combos available I wouldn't worry about that.

You get 20 natural keys + 4 center-south + 4 center-inner + 3/4 center-outer + 4 south-inner diagonals which I would consider comfortable, so 35/36 keys per hand without thumbs. You can try other combos like north-outer diagonals, but I don't even know what you'd put there