What a brilliant idea for the theme; cookie clicker + gambling. And the idea of time limiting your "rounds" was really cool.
There's a major problem though; the second gamble option has an EV (expected value) above 0:
3 in 10 chance of winning 5x your cookies, that means if you have enough cookies to not go bust quickly, you can basically generate infinity cookies.
Think about if I played it 1000 times, I'm expected to get 300 wins (+400 cookies each time = 120k cookies) and 700 losses (700 x 100 = 70k cookies). Which is a profit of £50k cookies.
So I beat the game with this exploit quite quickly