Wow, this palette looks great (+the examples look amazing!) 🤩👌

FWIW, I put together a couple of "minified" versions of the palette initialisation, as I can definitely see others wanting to use this nice scheme
(the snippet below uses the recent PICO-8 updates that allow a table of values to be passed in one go)

-- sepia palette
-- (+rgby utility)
--pal({128,130,133,141,4,142,14,143,15,7,  8,139,12,10,1},1)

-- even smaller ver
pal({-16,-14,-11,-3,4,-2,14,-1,15,7,  8,-5,12,10,1},1)

-- test draw using pal
function _update()
cls()
for i=0,15 do
rectfill(i*8,50,i*8+7,58,i)
?i,i*8+1,60,10
end
end

...or just run this online example of this code.

'grats again on such a nice entry 😎👍