Here's my two cents on this matter.

Everyone knows there's a problem with the Weekend Ranked reward system right now, but I also don't think evaluating players based on their ending rank would work well because it just encourages lots of grinding (with a >50% WR you can just climb to any rank with enough matches).

Rewarding tryhard players - why should they? All competitive TCGs only reward players at the very top, I don't see why GU has to offer carrot sticks to players down the line in the form of increased monetary reward. Sure, it'll bring a temporary boost to the number of players joining the game, but these players are also the most likely to dump their tokens/cards whenever they can.

They've already mentioned why they don't want to extend the reward system to allow for players playing more games than the 25 over the weekend in the original blog post, and I do agree with it.