Give each champion Stat Points depending on their rarity. Common champs get the most points and Legendary champs get the least points, by default.

Stat Points are points that players can use to increase ANY of the champion's stats. The amount that the Stat Points increases depends entirely on the stat in question. For example, 1 Stat Point can increase HP by 50 but increases defense by 25, and speed by 1.

If there are any possible balancing issues with this feature, Plarium can simply set a cap on how much a stat can be increased by Stat Points. For example the max amount of Stat Points for speed is 10.

Stat Points can be reajusted at any time for free from the Total Stats page. This means that (for example) if you place a champion in your spiders team but their hp is 1 point lower than your spiderling tank, you won't need spend 3+ hours to shift gear between 10-20 different champs just to get their hp a bit higher while maintaining the rest of their stats. We can simply either adjust the Stat Points of the new champ or the spiderling tank.

Duplicate champions can be fed into the main champion to increase the amount of stat points they have available. To avoid balancing issues, a cap can be placed on the amount of times a champion can eat duplicates.