Strackonan

I am starting an escalation league this week starting at 500 points. I was thinking about either: poxbringer of nurgle (120) - witherstave - Favoured poxes 30 x plaguebearers (320) chromatic cogs (60) or gutrot spume (140) Putrid blightkings (160) Plague drones (200) to max on contagion points and summon a poxbringer/plaguebearers potentially on turn 2? Any thoughts or improvements would be appreciated