In playing 4x games, including this alpah, I find the rush build option a bit "too easy".  I mean, I use it all the time.  But I think it would make sense to add some other cost to go along with the credits deducted.  For example, a planet doing a rush build might see a temporary loss of morale or productivity (because you worked those poor citizens a bit harder to get that thing finished... and some of them need to rest). Or, constant rush orders, because of strain on the workforce, has a minor impact on ideology.

Basically, I'd like to seem some way to slow down the use of the buy up option.  I know this is a strategy used by some (and I use it too at times).  But you can just build up coins and then buy buildings every turn and fast track your planet almost entirely based on money without any consequence, which seems both strange and lacking in strategic depth. Adding some secondary effect would cause players to think to at least two issues before rushing (financial cost and social cost).  

Thoughts?