I believe ancient and mythic keys need to be buffed. Especially with IRL rates being 1USD per 1 Mil. Someone could buy someone a mythic key and get 5 mil in game and get a money pouch or 2 premium hoes. I wouldn't suggest making the prices better, but making the better prices more common.
Go to https://mccentral.org/community/forums/suggestions and create a post there! It'll be looked at and considered more than posting it in General Discussion.
I took the liberty of moving this to the suggestion section as redsapphire recommended since you seemed interested in doing so and it's better than making a whole-new thread for the same topic. I assume you are suggesting increasing the frequency of higher-tiered money pouches, but this would be an inconvenience for season revamps in the start. Increasing the commonality of higher-tiered money pouches means people with purchased keys (for the most part) would gain an even greater boost at the start of a season consequently due to more money received in total. It would also be unfair to have a higher chance at better-tiered money pouches and then get unlucky for a lower-tiered pouch; it seems much more reasonable to have a lower chance at better rewards. Money pouches already increase in value as the season progresses, so the amount within now, although not proportional to the economy, should still be significantly greater than, say, the start of the season. It's difficult to create this proportionality when each season is inherently different in terms of exchange rates, baltop, metas, etc. I main KitPvP, so maybe I'm wrong with the above and you can correct me. However, for IRL trades and keys, I always view it like this: keys give you a boost in the beginning of seasons or reward you with items you might want. Rewards are by chance and have risk. Making an IRL deal for an ancient key to, say, open that key for a compost bin is a risk. You might find one for much greater in /ah or not find one at all, so you take your chance at it in keys. I view this as the same in regards to opening a key later in the season and unluckily receiving something you don't want. This is why most people typically save keys for future seasons. For the hypothetical compost bin example, I used this as a way to establish my line of reasoning. I understand where you're coming from for sure, but I don't see any easy way to incorporate your suggestion. If you can come up with a better way that makes it proportional throughout the season, then that could work in my eyes. I don't think increasing the frequency of higher-tiered money pouches would be beneficial due to boosts in the beginning of seasons, which is where any money matters most. This is just my opinion.