Venoms Vs. Raiders in game against Plague Marines.

So I'm working on a list for a game tomorrow vs. a Plague Marine army and I was wondering which is the best way to kit out my MSU units. Originally I was thinking of putting Wyches in Venoms and zipping them around but I got to think about it, might it be worth putting the Wyches in Raiders and maybe taking a couple five man Warrior Units to put in Venoms?

My reasoning is I basically want the Wyches up in my Opponent's grill. Between moving at cruising speed and possibly boosting, the synergy doesn't seem very good with the Venoms and Wyches.

Some very basic math with a Venom shooting at Plague Marines:

Venom Vs. Plague Marines (65 points with extra SC) 2 HP
12 shots hitting with 8
8 hits = 4 wounds
1.3 Wounds after armour saves
.88 Wounds after FnP (If they have it)

Raider with a Dark Lance 3 HP
1 shot hitting 2/3 of the time = .66 Hits
.66 hit x 5/6 to wound = .55 Wounds
.37 Wounds after FnP if they have it

Against this particular army, Venom shots don't seem like they will do much. Having a few more DL's could help Vs. some Rhinos and maybe popping an Oblit or two because I believe they are T4 (correct me if I'm wrong).

I still like Venoms for taking out stuff like the GuO and I'm planning on taking some gun boats, but is it just generally better to run Wyches in Raiders now? Seems like at least Vs. this army though, Venoms aren't going to be affective shooting Vs. most of his units.

If your opponent is running a Nurgle themed list, I would be extremely surprised if they didn't give the mark of Nurgle to their Obliterators, raising them to T5 and giving them better resistance to Instant Death. My only specific advice would be to absolutely drown each squad in splinter fire until they are all dead, 1 or 2 Plague Marines running around late in the game is a real nuisance once you've lost a proportion of your firepower. Check out my post on this forum: Hexrifles For The Win!

Yeah, I've had a lot of success vs. Nurgle themed lists using a ton of poison. Not sure why I'm trying to mix it up lol.

My main opponent placed like 6th or 7th at a GT last year with his Nurgle army, and I've beaten him with my DE army most of the times I've played against him (though IMO DE are very well equipped to take on a Nurgle army). I'll probably end up just taking my traditional list even though this is a different player, but in the same gaming group.

A few Plague Marines can be soooo annoying. I had one Marine kill off a squad of six of my Bikers one game (one Arena Champion with an Agoniser as well). I was pretty raged... good luck, but it still happened. They can wrech some havoc in CC.