It'll be in different brackets weighted based on rarities and win rate. Some pay2win can't be completely removed from these games, it's also something that drives markets and volume forward, I.e. someone finding a super rare and high stats creature may want to sell it for 1000 hive because he's not that interested in competitive pvp, however someone actively playing highend competitive pvp on a daily basis may want to invest 1000 hive in that creature so they can utilise it in their battles against other players with similarly strong creatures.
Brackets means we will allow players to enter pvp with creatures of max purple/epic rarity vs others of similar stat rarity so you won't get wrecked by someone with the most expensive/rare creature but instead know that your opponent can't have much better creatures than you so it'll be more about tactics, strategy, knowledge and some luck. Weighted rewards means that lower rarity brackets will simply offer less rewards to top players than the higher rarity ones since those cost the most and are the rarest.
There'll be brackets for a lot of different things though, level restrictions (players can only pvp in this bracket if their healer and creatures are lvl 2-10), rarity restrictions on healer items and creatures and maybe even class/creature type restrictions/edition restrictions (alpha/beta/etc).
Well what I was hinting at is that do you favor being good at the game versus just having spent all your cash. If brackets are only meant to separate the rich from the poor, I think personally it kind of suck. If it separates the good players from the casual, it's another thing.
I can play Pokémon without spending thousands of dollars and can still win is where I'm getting at. On the other hand I still need a deck that costs money and some rarer cards on the market that's a given.
I think balancing things out makes the gamers stay long term. Though from what I understand you seem to understand this.