This looks like a very fun list to play with and against! It does look pretty good, Nurgle has a lot of synergy. Some things to consider. Keep in mind I'm not super experienced and don't play Nurgle, so take what's valuable and trash the rest.
There is not a huge amount of mobility. The Gorebeast Chariot and Plague Drones are your fast units, but both only have a movement of 8". I don't think there are a ton of choices for Nurgle in terms of speed, but just something to keep in mind. Also, your Plague Drones will benefit greatly from being close to your Herald with their Locus of Contagion ability, but they will probably outpace him a bit. The Glottkin doesn't have the "Plaguebearer" keyword so he won't give them that ability.
The Plague Drones are doing double time as your mobile units and elite troops. Are you going to run them as one large unit or multiple smaller units? possibly consider running them as 2-3 smaller units to get them into combats across the board.
You are right, the Gorebeast chariot is a good chariot for AOS, most aren't spectacular. However, its main benefits come from charging (as with most chariots), but because of the roll for initiative happening each turn, you can't really guarantee you will be the one charging.
Consider increasing the number of Plaguebearers. At 20 or more models their Cloud of Flies ability gets significantly better. Starting at 20 models means this benefit will probably only last turn 1.
You don't have a huge model count, which is fine. But objective games which require certain amounts of models to be in an area could prove difficult. If you are going by SCGT standards, then 2/3rds of your army is concentrated in 10 models: the Glottkin and the Drones. The rest of your models are rather slow.
However, AoS is definitely about having fun. Bring whatever you want! This definitely looks like a fun list to play against, I would love to see it in action.