56 minutes ago, costi said:The fun begins when you play several different missions in the course of a tournament, and you need to take all of them into account when building your list.
You're changing the problem parameters (instead of 'what's the best list to kill your enemy with' you get 'what's the best list to do X, Y and Z'). This alone in no way guarantees that there won't be a couple of solutions that are significantly better than others,thus creating a meta.
Look at Armada and 40k for example. Do these strike you as games with no meta ?