I also play vanilla marines against Dave & company. I've really only been playing for about a year-and-a-half but have gotten fairly decent with them.
That's a good starting list you have, actually not too far off from what I take, but here are some of my thoughts:
As others have said here, you should take some hunters...at least two...limit where your opponent can fly and make him think twice about where his aircraft can hit.
I usually only take one Tactical Detachment. Mostly just personal taste, Tacticals are expensive at 300 pts and I like to take more specialized units.
You might want to think twice about the strategy of putting 2 Assault Detachments in the Thunderhawk. There are some armies in Epic designed for close combat (like Orcs and Tyranids) that will hit you back as hard - or harder - than you hit them. I'd do 1 assault and 1 devastator. (Also, it seems whenever I hit with assault marines & chaplain out of a Thunderhawk, the chaplain NEVER hits with his macro, and ALWAYS dies before rolling for combat resolution.)
I don't take Vindicators. First off, I flat-out don't have the models, but I also don't picture them as being all that effective and I instead spend the points on anti-armor Predators. No doubt Dave can argue with me and point out the value of Vindicators, they're just not my thing.
Terminators - I (almost always) never leave home without them. But the smart way to play Terminators is to not have them teleport in until turn 2 - to limited how much opponent scouts can move out - and you really want to hit hard and really stack the odds in your favor where they hit. I always take a chaplain with terminators to give that extra macro in HtH and the extra +1 in combat resolution. As others around here can attest to, I have an uncanny ability to hit with at least 3 out of 4 close combat attacks, and then hit with all 5 macro attacks - which can really mess a unit up!
The big downside to Termies is after hitting hard, they aren't really very mobile so you want to have them come in somewhere that they can affect the game after their initial attack -- maybe even pick them up in your Thunderhawk at end of turn 2 so they can redeploy and hit again in turn 3.
One unit of scouts is good, but 2 are better. I usually don't take the sniper upgrade for scouts - again, matter of personal taste but I just find it never works and I can better spend those points elsewhere - but 2 units of scouts can ZoC a lot of the enemy and really mess with his plans.
As Dave said, Drop Pods can be a lot of fun but I'd hold off until you get a good feel for the game. They take a lot of foresight and planning, and even then things don't always work out right and you end up with your ass hanging out. Also, if you play in a tournament or something where you have to write up for list beforehand with no idea who you are going to fight - and then end up going against Tyranids or Orcs - having drop pods is just playing into your opponent's hands. I've played with drop pods, they're fun and Dave really knows how to play them well, but I don't think I've won a game with them.
Hopefully you'll be able to make it to our next big gathering
