Well, the number required per increase changes. haven't quite worked out the algorithm. Not sure if it increases by planet level or total or something.
In the spirit of this being a self-proclaimed 'Idle' game as indicated by the title, would you consider a "Buy All (Low-to-High)" button on the upgrade window that would automatically purchase all available upgrades starting from the lowest? I'd like to put forth the idea that you include a check-box for "auto purchase", but that would probably just make us lazy!
You should consider making the gold bonus a percentage instead of a flat amount. Otherwise, there's no point in fighting anything other than the level you can kill in one hit.
Seems like you could set a requirement (like max level attained or money cost) for a soft reset and increase the max level by 10 with the reset, enabling more research points.
Would be cool if there was a tooltip or a hover-over option to see what your net gain/loss per resource is per minute. I try to balance everything out when I go idle, but if I could see +5 ore/minute or -1 ore/minute, that would help a lot. good stuff
 "The Pix"){kind=icon}
 "Idle Gems"){kind=icon}
 "Cosmos Clicker 2"){kind=icon}
 "Idle Necromancer"){kind=icon}
 "Metamorphosis"){kind=icon}
 "Save the Earth! - The Incremental -"){kind=icon}
 "Troll Clicker"){kind=icon}
 "AdVenture Capitalist"){kind=icon}
 "Clicker Heroes"){kind=icon}
 "Idle Blacksmith"){kind=icon}
 "Slimilization"){kind=icon}
 "Idle Village"){kind=icon}
 "Executioner 2"){kind=icon}
 "Mark Of Darkness"){kind=icon}
 "IdleSpace"){kind=icon}
 "Idle Shop"){kind=icon}
With another click on item/button or via Buy/Cancel button.