Buy the first 3 rewards and ignore the others for a little while. Better tier spawns will help a ton. Energy is also pretty important so when you get to that point work on increasing gains for it.
only if you could maybe control units 1 at a time by clicking them so you can cnipe with them instead of them just running out and getting killed by the turrent
well, SAuqn6L4n6iBjqvCjowW to you too, bro.