I’m kind of in the middle on this. A lot of people complain about these issues without going into proper depth with their suggestions. Instead, they often just pull up videos of nortorious duping youtube channels and follow the herd mentality to agree with them, their fanbase, without really considering the bigger picture. Servers that aren't in the big leagues of Hypixel still need to have cash flows, even if the methods implemented aren't always popular. When I say "proper depth", I mean genuinely thought-out suggestions - not just vague examples or surface level criticism.
I can understand the frustration of not getting what you want repeatedly, but at the same time, the server does need funding to keep running. Personally, I think the Classic, Vote, Pinata, Rank, and Fortune crates are fine staying as they are, with random items given. I know that some people will continue to argue that it's “gambling,” but that’s just my personal opinion to keep it that way.
One suggestion I have is for the Monthly crate, to help differentiate it from the others. Instead of a single reward, it could give two items: a guaranteed random cosmetic, along with a chance (not guaranteed) to receive a minion. If you don't get a minion, the second reward could instead be something like cash notes or a spawner.
From a cosmetics perspective, I also think it would be more appealing to introduce
Nexo to Oneblock, Survival, and Creative. In my opinion, it offers much better-looking custom models:
https://docs.nexomc.com/
Nexo allows for custom furniture, armour, and a wide variety of other custom features. Essentially, it can provide the same type of custom cosmetics on the Parkour server — and even more. Below are just a two examples, both of which are 100% vanilla Minecraft and require no mods.
These are just two small examples, but there’s a huge range of custom models available. Nowadays, I believe cosmetics tend to be viewed as less “gamble-y”, if you will. To avoid repeatedly receiving the same cosmetic, I think there should be an NPC linked to the crates where you can trade one cosmetic for another of your choice. This would help prevent situations where you end up with, for example, four of the same chestplate.
TL;DR
I’m neutral on the issue: while crate frustration is understandable, servers still need revenue. The existing crates are fine as random rewards. To improve things, the Monthly crate could give a guaranteed cosmetic plus a chance at a minion (or cash/spawner instead). Introducing Nexo cosmetics across more gamemodes would make rewards feel less “gamble-y,” and adding an NPC to trade duplicate cosmetics would prevent repeated unwanted items.