right. the idea is to further merge items so that the list is not so long for those single craft items. the maintain item should definitely remain separate.
as far as crafting order goes, yeah I can see it being a problem when you craft 3 of an item while there are 5 more of that item requested in another build, but those first 3 were taken and installed into the wrong building so the order for that building would be pointless if you went from one set of building orders to another, rather than just ordering the items like vanilla does 1 item type at a time in the queue list. in other words, the order that the single item type is crafted in is not important. what is important is tracking if the building has need of that item in the queue anymore or not and updating it accordingly to ensure that the color group for each build is active in the queue while it is still requesting the item. now to do that means the items that have just been crafted need to be assigned to a build immediately. if there is an item available in storage then the crafter would need to subtract the number of unassigned items in storage and wait to see if they will be used or not, and if the number of items in storage is lower than the required number, then it will craft what is needed to fill the build order. assigning items that have just been crafted to a build makes sense for items that are not maintained, but causes problems for items you are building just for trade.
it may be simpler to introduce a new ui element that is specifically for choosing what you intend to do with the item you are crafting so that the path for the items is much more linear. this way you can choose whether the item will be used in a build, be maintained, go to storage, or be used in trade.
I actually did make a suggestion thread, I’m going to add this to it actually. if you want to join me over there that’d be swell. I’ve not done any modding to SH but I like thinking of ideas like this