https://www.manutd.com/europeanaway
I hate to say it - but away tickets are where that other lot do things better than City. (On transparency at least).
I think fans would benefit on knowing where they stand in the pecking order, which United's communication clarifies.
I usually base my thinking on the points criterion, which is often, but not always, an indication of when a match will sell out.
It would save people extra cost on potentially wasted transport and accommodation costs as they would better be able to judge the risks.
Simple information on how many are at each points level and how many are on cup schemes would be beneficial, imho.