Just going to add onto this.
Here's my vision of how mod queues would work.
First of all, Challenge queues are terrible. Like, seriously, nobody should have to put that much extra work to get their map looked at.
What would happen is that the forum would be how it is now, with thread titles, stuff like that, but there would be an automated counter that would show how many maps are currently in the queue (A limit set by the queue owner, with infinite being possible)
Upon clicking on the thread, people would be taken to a screen like this (image created by LesTrucsRose. Previously was going to be used for my mod queue but then stuff happened and tl;dr my queue is the same as it was)
Under the title, there could be an area for rules, where the page administrator can write a set of rules for their queue.
If there is an open slot, then mappers can submit their beatmap to the queue, and it will be listed there.
Page Administration:
The administrator of the mod queue (whoever created the thread) would have the ability to remove maps from the mod queue upon completion of modding a map. The administrator will also have the ability to blacklist people by username, change the limit of maps in a queue, open/close the queue, and add other administrators (for instance, if I were to transfer my current queue into this format, I would be main page admin, and then Gabe and Zurrrr would be Sub-Admins. Sub-Admins would have the same abilities as the main admin, except they cannot add other admins.).
The biggest benefit of this is that people who run mod queues will have the ability to consistently have maps coming in for them to mod. This takes out the hassle of getting maps from only certain regions due to time differences, and having queues open for only 15 seconds or something. If there is a need to close a mod queue (ie. The admin of a solo mod queue is going on vacation and can't mod maps), then the ability to do that is there, as well as re-open.
The only disbenefit to this is that this will only work swimmingly for regular mod queues. There is no automated way to check if someone has mod4modded in a mod4mod queue, and there's no way to restrict those in a challenge queue. But both of those, I'm completely against, so meh o-o.
I'd be happy to make a more organized and in-depth explanation of this :3~.
Also, maybe you should move this to Feature Requests?