Stack distribution is the biggest factor, yes. If you’re the shortest stack and there’s no reasonable chance of someone else busting before you (i.e. you have 12bb and the next shortest has 35bb) then going with Nash ranges/exploitative cEV ranges isn’t going to hurt you much. But if you have 12bb and another guy has 3bb, you should be way, way tighter than cEV Nash ranges.

There’s a lot of value still attached to having fold equity – so putting in the last bet still gives you some leeway – but especially when you’re the one calling it off, you need to be factoring in all the stacks around you before deciding on how much value there is in accumulating further chips. The shorter other players are, the more you gain from staying where you are.

Get yourself a copy of HoldemResources Calculator – this will basically solve a lot of your ICM queries. It can do cEV Nash, cEV exploits, ICM Nash and ICM exploits, and you’ll be surprised some of the crazy dynamics that happen when you have a reasonable idea of how other players are going to react to ICM situations.