General reccomendations:
Speaker Wire/Interconnects - Try to get a 100ft spool of 12 or 14awg wire instead of taking it for granted.. banana plugs make connections a lot easier on that note. Otherwise I mostly just reccomend something that gets decent reviews. Give Monoprice.com a shot if you're in USA.
Subwoofer - If going with a large ported design, contact the manufacturer to see what the tuning frequency is. A low tuned ported woofer will murk sealed subs for the same purposes (HT). I'm sure you've already looked at the SVS and HSUs of the world, but on that note I reccomend taking a quick look at elemental designs' DIY kits. the 180 dollar kit with a Dayton SA240 plate amp from partsexpress should run you around 300 dollars or so total, as long as you're okay with not veneering it to make it look "pretty", you'll probably have a subwoofer that royally impresses many people
Receiver - Marantz SR5003 refurb from Accessories4less. 90w of power, enough modern features, and as a guy who has an SR6003 myself, it just sound great for a receiver.
You might also want to look into the NR1505 but keep in mind that although it`s a 7.1 receiver, and 50 watts ain`t really all that bad, it lacks pre-outs so you can`t upgrade to a dedicated amp in the future. The 5003 could eventually be used as a preprocessor so you can get more power to your speakers with a better amp.
Room Treatments - Obviously I don't think you want to treat every inch of that room, but do look into adding some bass traps in the corners.
Speakers - the main part, right? Here's a few suggestions
Go to EMP's website, track down their clearance section, and see what you think of
1x EMP e5ti (PAIR)
1x EMP e5ci
1x EMP e5bi (PAIR)
1x EMP wall mount bracket or stand (Pair)
or go to Axiom's factory outlet and look for
2x Axiom M22 v3 (single)
1x Axiom VP 150 v3
2x Axiom M2 (single)
+ Stands or mount-brakets
OR go to Aperion and check out their Intimus 4Ts...
Another suggestion I have is some Klipsches from a brick and mortar shop. I was down at london drugs the other day and they had them on clearance. The thing about klipsches is that they'll go pretty loud without putting too much power into them.
One final reccomendation is to track down some totem rainmakers. I don't know if they sell them down in america but I was at a HT shop the other day and these things really blew me away with their.. i don't know what! They were just really great speakers, plain and simple, and their price was reasonable IIRC although i wasn`t really paying attention because it was a day after I`d filled out an order for an e55ti set and the salesman was kind of annoying me with his pushy-ness..
The Epik looks unbelievably awesome, but for my price range I'd have to sacrifice on the front speakers and I'm not sure how much I want to sacrifice there. Also, the subwoofer is going right behind my chair, and as much as I like strong punchy bass, I don't know if I'm looking for room-shaking necessarily... Does that makes sense or am I making a mistake?
well, if we`re talkin about a movie-centric HT, I think the sub is the part that you`re `notice` even moreso than surrounds or L/R fronts. The sub and your center are just really important pieces that you shouldn't overlook. On that note you might also want to look into some Emotiva speakers.
Also, do consider that you have to play around with sub placement anyways in order to get a clean response... my overall point is that your sub could make-or-break your entire home theatre... ask yourself this
"What is the point of any speaker system"
and you should probably answer
"To reproduce what the source creator originally produced".
In the case of action flicks or even epics fantasies like Lord of the Rings, that low freqeuncy effects channel isn't just a one-note boom or a subtle drum in the background.. it's truly its own channel. You wouldn't want, say, your rear surrounds to be extra-quiet and have a sharp decline at, say, 250hz, with the caveat that your front mains are ever-so-slightly-better.
Just like you want rear surrounds to be fairly flat down to 80hz or so, you should want a sub that's flat at least down to around 20hz (actually, ideally tuned somewhere around 15 but you won't get that in your price range) and reproduces the sounds well, as they were created. And likewise, just like you want surrounds you can hear, you should want a subwoofer that's going to be heard if it's meant to be heard!