Being f2p isn't that hard. It really needs to stop being used as a) a badge of honour. b) the reason why you aren't at the top of your arena.
If you are carefully planning how you use what then you can v easily take top spots in many aspects of the game, except the ones CAW patrol occupies because there are constant posts here reminding me that they are the coolest.
If you're consistently taking time off from the game?
You're not realistically going to take top spots in arena. That's just how the game works and money spent by others isn't even close to being a primary factor.
I'd suggest working on aspects you enjoy about the game, GAC might be good because taking time away has less of an impact here.
If you really want to become competitive then take a deep breath and work on a GL, it'll take you a year but a 500+ speed toon that can't be stunned and stat builds throughout a battle is not leaving the meta any time soon.