Rapid Escalation (First Steam Prototype)

Thanks for the honest feedback. I like the idea of the seconds added, but will have to think if this will fit in the vision of the game. I do have a question on the upgrade tree for you: Currently the upgrade tree is kind of open to buy anything of you have the money. This is an open upgrade tree. So my question is, do you think a more closed/linear type upgrade tree would work beter for gameplay? Like the upgrade trees we get in these other incremental games?