Huh, I had forgotten there were autosliders, I remember trying it time or two and it totally messed my IC usage, then stopped using it... Why on earth would you want to 'use the needed amount' on any slider anyways, most of time I'm using less than I'd need on everything...
Dissent below 1% -> drop cons goods to create dissent (you might get event, don't want to waste those)
Production -> always overqueue, things you are producing as singles (big ships, factories) in the bottom so 'leftover production IC' goes to those and you don't lose geared up ones, nothing to worry about...
Supplies -> 'ballpark figure' unless it goes below 1k, it hardly matters how much you have
Reinforcements; this is usually set to about 1/3rd of the need, I'll allow waste of 5ic on majors situationally, if I get some slow moment and don't bother...
Upgrades; like 10% of needed goes to here, those infantry divisions will upgrade over time, no need to rush over producing new new new.... (And half a year later you can fix it back to 0 so things don't go to waste)
Priorities, eh, dissent & supplies for me, seems other people freak about reinforcements, I suppose keeping that on the white is harder than others, I hardly need to change the sliders more often than when I put new productions in the queue, always check them then anyways..