Before I start, they won't be able to be stacked in a players inventory.
It would be cool if pots were made stackable when in chests, hoppers etc. This would allow for pots to be auto sorted, more storage for potions etc etc..
It would be a lot more simple if I didn't have to have tons of chests for pots I could fit in 1 double (if they were stacked).
There could be a problem with getting them from being stacked in a chest, to being unstacked in your inven.. Maybe you could be able to drag them out along your inven?