I was planning a nurgle beastman army using nids a while back, with genestealers as gors & ungors, trying to make them more insect like. I guess they'd work better now with as gors, with the 2 tallons counting as 2 hand weapons. Spears might not work so good. Gaunts would be pulling charriots, and gaunt/stealer centaury conversions for centigors.
In the end I decided it would be too tough and went with kroot beastmen instead