I just finished a Nurgle campaign and I think the popular sentiment that he's the weakest faction in WH3 campaign is just off-base.
It is off-base, indeed.
Nurgle is one of the strongest factions IN BATTLE (and thus, in MP) for a reason.
The combination of high HP, good resistances, lots of regen and
poison everywhere is just pretty insane. Not OP, but, you know, up there.
But yes, Nurgle gets shafted hard in campaign for reasons you listed.
Terrible autoresolve (autoresolve doesn't seem to take poison into account at all), terrible growth*, terrible replenishment, gets bum-rushed by ordertide from the get-go.
It's on par with how bad VCoast was in WH2, especially Cylostra.
* Seriously, Is it anyhow possible to get T5 building before turn 70 or so?
I have large amounts of cash in campaign, but nothing to spend them on
That growth is so absurdly slow.
Meanwhile, Kislev goes for me with full elemental bear stacks...
I'm not losing, don't get me wrong. But it's so weird to be assaulted by highest-tier stacks while I'm not even close to that.
Yes, you can get to T5 before turn 70. Looking through my save files, I hit T5 at turn 61. I could have hit it faster with more scrupulous use of Pox:
Yeah, I was thinking I probably didn't use plagues to full efficiency.
One thing I noticed to help a lot at the start of the game was this:
The starting war with the Ogre faction is a trap. Only take your initial province from them,
don't spend any of the money you get, and then use that money (around 10k) to make peace with the Ogre faction.
That basically makes sure the Ogres will leave you in peace for a very long time, and might even become friendly. So then you "only" have to deal with the ordertide.
The biggest mistake you can make is chase the Ogres east, causing the other Ogre factions to slowly turn more and more aggressive towards you. You don't want that.
My biggest struggle re: bum rushing was a visit from this rogue army asshole while Ku'gath was far up to the northeast. The two stacks in garrison are just nurgling garbage plus seven plaguebearers.
I had similar things happen, but with the dwarven factions. At around turn 15 or so, a stack full of T2 Dwarves around your capital is no joke.
Thankfully, Nurgle towers are awesome and dwarves are slow...
Generally speaking how do you efficienctly deal with towers in settlements defended by a reasonably sized AI army?
As Nurgle?
Plagues. There's this one effect that gives garrisons attrition. Launch that at a city 2-3 turns before your army gets there. Much easier to deal with.
You'll still lose troops, of course. But you're Nurgle, you don't really care if you lose anything that isn't high tier.
You can also do a normal siege for 1-2 turns to build some siege equipment, in that time the garrison will dwindle even quicker.
All of that means their army losses penalty will trigger a lot faster, meaning you'll get shot at for a shorter duration, losing less troops.
Alternatively, you can cheese-win settlement battles with fast troops. Lure enemies with a main force, while taking victory points with the fast ones.
Okay, "fast" ones for Nurgle.
One thing to note is that while the solution to everything with Nurgle seems to be plagues, your income of infections will be VERY low at the start of the game. So, yeah, while you can solve everything with plagues in theory, you'll need to pick your targets carefully to begin with.
And very likely, most of the early plagues will go into your own growth.