It'd be great to have conditional accessories. This would only really apply to tools and a few other items, however it is still useful to ensure something isn't forgotten.
I imagine it to work something like this:
Some products require certain tools to put together. If the product is added, regardless of the amount, one of the tool needed is added as an accessory. Instead of adding multiple tools as the product count increases.
It doesn't happen often, however sometimes it majorly affects a job is a tool is forgotten by the prep team. This feature would just assure that nothing is forgotten.
This is getting my vote!
Just to follow on from what you've said, I work for a live events company and this would work great for me, my examples of this would be:
We own 84 of a type of uplighter and they live in 12's within bespoke made flight cases and at the moment we have to remember to manually add the quantity of cases separately, the conditional accessory for me would be 1-12 lights = 1 case, 13-24 lights = 2 cases and so on.
My other example of this (not sure if this would be useful for others) would be:
If my opportunity had uplighters and a lighting desk it would auto add the wireless DMX transmitter for the uplighters.
I think it would also be great if when setting up your conditional accessories you had a similar window to the 'standard' accessories where by you could determine weather your conditional accessory needed to be Default, Mandatory or Optional.