Sorry for the slight threadomancy, but it's only been cold for just under a month so I figured it was still fair game.
If you're interested in some "fluffy" marine profiles (and by extention, an unbalanced but nonetheless fun game), then I'd suggest you see if you can't get your hands on a copy of WD 300 (US Jan 2005 issue), which had an army list for "movie marines." Very much like your proposed list, this "army" is a 10-man tactical squad. I don't want to give out full profiles, since I'm pretty sure that's against the rules, but just to give you a taste the Space Marine Sergeant, your only HQ option, has stats closer to Marneus Calgar than to a Force Commander. Your standard marine falls somewhere in between a Captain and Force Commander (with beefed up S and T). Marines' weapon stats are seriously upgraded to the point that a bolter functions a lot like an assault cannon, and a Rhino looks more like a Land Raider on paper. They're all functionally independent characters, and they have some special rules to boot. My personal favorite is an "I'm taking you with me" type of rule where if a marine is killed in melee he can opt to either make one last attack with his bolter or detonate his grenade, centering the blast on himself.
Anyways, the point being, if you're at all interested in some truescale marine rules, these are frankly not too far off from some of the ridiculousness going on in the fluff.