The problem is that you need to spend at least 5k on Rebellion to have the cards and you are near sure that the values of your cards will drop off a cliff once the new set comes out and a lot more when it gets dumped into wild. So basically you are spending a ton of time to only earn a small part of the price decrease back.
This dynamic makes it impossible to further invest in the game. I hope they start putting some effort in fixing the issue of declining card prices.