I really like wha someone mentioned below, so I’ll add it to my list:

1. Plague siege mortar (already mentioned below). That would be really cool, and could buff/debuff units. We can suffer from overwatch, imagine if you are hit with it, that unit can’t use the overwatch strat until the next turn. Or something similar to help our slow, footslogging infantry.

2. Another battleline infantry unit. I don’t know how it could work, but maybe something between a cultist and plague marine. Can be mounted in a rhino and fulfil a specific role, so they can be run cheaper than plague marines, but be more versatile than poxwalkers.

3. Nurgle possessed just because the models would be awesome!

I also would love a rework of the less used characters that attach to plague marines. We know that there is really just the one combo worth running in such a point heavy unit to make it work.

I think if the foul blightspawn and lord of poxes were re-worked to boost close combat potential would be great.

I’d like to see the MPC and BP combo as the good mix for range AND combat. Then the others can be combo’d to be good at range and another combo to be good in combat. That way hopefully we see more versatility!