Why not make the cookie variety upgrade linear? Then we could effectively upgrade each cookie tier within sets efficiently.
The ability to turn off a cookie set would be great. Then we could maximize production. To make this balanced, just have it made so that only a complete cookie set can be turned off
Since upgrades in the upgrade screen are bound to be added, why not start splitting the upgrades screen into sectioned parts. Sections like "Rainbow Storms", "Cookie Collection", "CPS", and "Miscellaneous". Also a new idea for an upgrade, "Slow Swipe", which slows down the rate the screen swipe travels down the screen, allowing for possible back to back screen swiping
Finally, make the alternating cookie upgrade cap at the nut cookies. Then it wouldn't be so hard to get it while the upgrades keep rolling out
As for a new set.....
color: red, orange, yellow, green, blue, purple, black, white
Shape: triangle, rectangle, pentagon, hexagon, heptagon, octagon, nonagon, decagon
Metal: copper, iron, cobalt, nickel, titanium, silver, gold, platinum