Regardless of being a F2P or P2W player, you should prioritize your Zone Comm Tech. If there’s one thing I recommend you buy in this game, it would be a single pack of 7000 courage medals. This will allow you to unlock box 4/5/6 as well as 100% Arms Expert.
The more CoZ boxes you get on a daily basis, the more courage medals you get, which goes back into Zone Comm Tech. It’s a positive feedback loop. The 100% Arms Expert is basically equivalent to having a 100% ticket on all the time.
As you go down the tree, you’ll research additional boxes (7/8/9) as well as additional point multipliers and then eventually, double rewards. A full Zone Comm Tech tree will give you a point multiplier of 400% + 100% ticket = 500%.
I bought a package of 7000 courage medals about 2 months ago now, and grinding the daily CoZ boxes, I’m at 92% Zone Comm now. I should be maxed by the end of this season for sure.
Maxing your Zone Comm ensures yourself sustainable growth in this game. The courage medals, money, resources obtained, really do help. Especially since courage medals are required for late game research.