I'm very surprised, all this planning and you haven't even mentioned the sub-woofer enclosure. That is going to be the single most important component to your system. You can put a $1,000 sub woofer in some off the shelf box and it'll sound like ****, matter of a fact a $20 sub woofer would probably out perform it. Stay away from sealed & bandpass. Look into a PNR ported enclosure. I just picked up an Obcon single 12" enclosure (just over 2 cu-ft) and it's nearly 5db louder than my off the self slot ported dual 12" enclosure was..with 2 12's. I know 5db may seem like a small number in the audio world that is a HUGE gain.
Think of it this way..say you have a size 12 shoe...would you feel comfortable slipping into a size 7?..no. So the enclosure is VERY important it can either make or break a system.
May I ask why sealed should not be considered? I agree, a bandpass is not something I would do since it has a steep roll off. A ported enclosure will indeed have more output than a sealed enclosure but there are also trade offs. With a sealed enclosure you dont have to worry about tuning frequency or even the frequency the sub plays. If you have a ported enclosure and don't have your SSF set on the amp, and if you play something below the ports tuning frequency, well, time to shop again for another woofer. Also, ported will require m ore space and will not have as much power handling.
With the sealed enclosure you will get much better lows, but that also depends on the subwoofer. Some subs also work better sealed, others work better ported. I used to be a big time ported fan but once I tried sealed again, and a proper enclosure for being sealed, I will never go back to ported. Sealed can still give you plenty of output but the sound will be much smoother and not as boomy as ported, so the music sounds more natural.
To the OP, have you decided what to get yet? BTW, you can fit 10's in the doors if you really wanted (seen it done in person) just takes some (well a lot) of modding. If you have a 1/2" baffle made of MDF that uses the same trace as the stock plastic baffle, you can fit a speaker with the mounting depth of 2.54" without a problem. You might be able to stretch that by a few hundredths, but not much more. As lashlee mentioned, the basket on the speaker may be too big. On my DLS Iridiums, it was just perfect (thought I had to make the baffle opening larger). For my Zapco CK's, the depth is close to 2.9" so the baffle has to be thicker. Even with the proper thickness the basket hits the door so I had to cut it a little with a jigsaw. Now they fit perfectly.
You might be okay with a 3/4" baffle, not quite too sure, but IMO it's best to stick with the 1/2" since the speaker won't be hitting the grill on the door panel and you won't have issues getting the door panel back on and to stay in place.
Lashlee, didn't know you were here too...nice to see another DIYMA memebr
Oh, as for the rear speakers, don't even worry about those. I have mine taken out. Sounds much better without them there because the music is in front of you, rather than behind or next you.