@Sarmatian123: I guess you could mod in bank as custom workshop? Add in reactions to convert 100 of thing to thing token (say, a tool item with no use) and back, and thus reduce the clutter while still having the resources as needed.
I have clutter with logs (7761), stones (19321), blocks (948/
26759), ammunition (17319) and plants (14379) and out of those the 3 first generate lag, when browsing the values in z-stockpile menu. Bars I have so far mere 5511 of which 3781 are metal bars. So problem with clutter is not so huge actually. Each caravan adds only 100 bars yearly to stockpile more or less. So this is a problem I let be for now.
Though your solution combined with "bank" process in smelter making "gold bars [25]" out of 25 gold bars passed my thought. I could add such a process into smelter in vanilla save by sacrificing slot of some "dumb" process. Though can you imagine Dwarf dragging "copper bars [645]"? The weight lol. Also, I am not sure, if crafting process will not consume whole fussed stack.
Currently I am making claystone mechanisms and diorite tables amass to remove some stones. Everything non-master gets atom smashed and the rest ends with caravan. I am puzzled how to solve lag from
26759 blocks already placed in construction. Should I forbid them? Hide them? Actually I can not for some reason even turn f:forbid on 19964 granite blocks from z-menu.
It seems, everywhere, there are involved stacks of items instead of single items, the lag impact on game is lesser.
Shouldn't connected with each other x constructed same material type blocks to be considered just 1 single item of that block [ "x" ] ? Map rewrite will be soon. I hope Toady will fix this lag from constructed blocks then.