This was going to be posted in feedback, but for some reason I'm not able to post there. So here will have to do instead.
I'd like to see the removal of cats and the increase in xp speed by +100% so that it would be as if someone was on cats all the time. Which is the case for a lot of people anyway.
Getting rid of cats as above would free up the space in your GHs, apartments, packers and bag. It would save people having to try and clear out their GHs so often so they have more space for actual mats and equipment. It would also save people having to leave a hunt so as to get cats for someone, I know a lot of people don't mind giving out cats but there are times when you could do without having to.
The removal of cats and the increase in xp speed (+100%) should be both easy things to fix.
Moving on to dyes, this would be harder to implement but should be still doable. The dye (object) is created ingame and then added to an armor piece (2nd object) with alters the color attribute of the 2nd object effectively creating a 3rd object. Long time since I've done any object programming and it probably shows.
Why dyes, mainly because we have a good crafting system but the stats are fixed to the type of mats including the color. So we end up with a lot of white or black armor because the stats are better.
Basic armor could have just 1 color attribute, medium quality 2 (2 sets of color zones) and high quality 3 (3 sets of color zones). I say zones because a color attribute may be present in more than one area on the armor.