Paying equals a better outcome sadly.
Do not pay on every game, such as Mech Arena. The reason is that the items you pay for are most likely useless and degraded in a snap. Also, the game is constantly updating which will extremely influence you to pay even more. Also, the developers are only interested in money money money, so they are going to whatever they want, in order for you to pay, otherwise, they will mess the game up for you secretly. I saw it in other games and now I'm seeing it in this one.
EDIT:
Do not pay on every game you play. However, you can pay on Mech Arena if you want. The reason is that Mech Arena needs the money to make updates to benefit us. As of now, the updates have not been that good. Well, to create better ones, they need more money. Hate to break it to you and me, but we just got to pay, if not, then no Mech Arena. Yes, they nerf weapons which is not always fun, but they are still creating new weapons, sometimes even better ones. However, they stay as weapons for purchasing, for way too long. It should stay for only 2 weeks at best. Yes, they can do whatever they want because it's their game, I just hope they make good choices. They are starting to make the game better with the tests for matchmaking. I like random maps for 5v5 and a limited number of battles for ffa. Keep it going mech arena, don't disappoint.