Returning to Death Guard

[Willeth the Brave]

Hello there,

I have had two death guard armies in the past (for 4th and 5th edition), but have decided recently to start anew, because, well, I sold all my old minis! I was wondering if some of you could give me some list advice. I'm not looking for anything overly competitive, as I prefer a more fluffy list and I often pick units because of how the models look. Anyway, I was thinking of starting small with a 500 point lists, and building from there. At my local gaming club most armies are represented, so I'm trying to go for a versatile list.

Here's a rough idea of what I'd like to field (so far I only have a converted DV lord and a rhino):

HQ

Lord Putridum: 135

Chaos Lord: 65

Mark of Nurgle: 15

Power weapon: 15

Plasma pistol: 15

Sigil of corruption: 25

Troops

Squad Foetida: 200

Plague Marine squad: 120

2 meltaguns: 20

Rhino: 35

Power fist: 25

Squad rancidum: 165

Plague marine squad: 120

2 plasma guns: 30

Power weapon: 15

Is the power weapon worth it in the plasma squad? Seeing as they will be objective sitters. Also, are power fists as useful as melta bombs for tank busting? My reasoning was that with a power fist a champion would deal out multiple S8 hits. Instead of a second PM squad at this point value, would it make more sense to get a larger squad of cultists? Any suggestions would be great Thanks!