I guess there's an R1 delete key in the base set, but I agree that it would be nice for the 40s kit to have a R1 Backspace to support 5-row ortho boards like the Preonic, Nyquist, Iris, etc.
For the caps, worst case there's a R3 Code key in the base set, but that would also be nice to have in order to make this a fully compatible ortho kit too. I think those two keys are all that's missing to support those larger ortho boards. I guess those aren't 40s really but it could be a 40s/split/ortho kit!
Not a fan of R1 Backspace for the Preonic, it kind of goes against the idea of not moving your hands out of the homerow.
I will think about the R3 Caps lock.
I'd like to see dark gray highlight keys in the 40s kit (similar to Jamón). I think you hinted that you would do this anyway.
I'm also a fan of the larger spacebar kit that you currently have on the Nautilus Nightmares page, but I'm not overly attached to that and I could definitely believe that the price would be a good reason to shrink it for a majority of people. Would be nice to leave a blank R4 1.25 somewhere in either the 40s kit or the spacebars kit.
Other than that though, no complaints. I think you absolutely nailed the kits with Jamón. The flexibility and coverage is simply incredible and it sounds like the pricing will be too!
But the real question is: where is the Nautilus Nightmares matching Percebe?
40s will be made more or less like Jamón, I have to think about it: is it really worth it to add all those keys or should we go a little bit cheaper? Right now we get two groups of people with just that kit since it has all the split spacebars and the second B, so maybe I should consider making it smaller. It will depend on how well the kit does with Jamón.
Regarding Percebe, preparing for Jamón, Verne, MT3 Serika, and my daily dose of procrastination postponed Percebe maybe a month or two, but we are back on track with that project. You should have news about it sooner or later. There's no rush for a Nautilus Nightmares edition of that board since this set won't drop until Q4 of this year.