[uncle duncan]

The number of simultaneous inputs you need will dictate your interface. I like the Motu stuff on a Mac, with Digital Performer. Their interfaces give you zero latency monitoring of inputs, and DP gives you automatic delay compensation for plugins. PTLE doesn't. PTLE is the worst possible choice for a DAW. But many people buy it for the PT name. Or for compatibility with other studios, which doesn't sound like it's going to be a factor with your setup.
But back to interfaces, most non-PTLE interfaces do give you zero latency monitoring of inputs, so it's not like you're limited to Motu.
One option to consider would be a Alesis HD24 hard disk recorder for tracking, a Yamaha 01V96 digital mixer for monitoring all 24 tracks via adat lightpipe, plus you could use the 12 built-in mic preamps going directly into the back of the HD24, using the inserts. This doesn't affect the individual channels on the mixer. You still have 32 channels. The pres on the 01V96 are decent. (Phantom power in groups of 4.)
Then you could get a motu 2408 interface, which has 24 channels of adat i/o, with one bank switchable to analog, and transfer tracks from the HD24 into the Mac for automation and mixing, using the 01v96 faders, eq, dynamics, and doing your volume automation of individual tracks in the Mac. (The 01v96 can only do automation via a computer sequencer, but it does have 99 scene recall, so you can revisit your mixes later, after each individual band member tells you he wants his instrument louder than everyone elses.)
The nice thing about the mixer is, when you're tracking, you can set up 4 seperate headphone mixes, (zero latency) and you don't need to fiddle around with a mouse to tweak those mixes. Personally, I think doing everything with a mouse is about the most difficult way to work, which is why so many companies make control surfaces for computer DAW's. But those control surfaces cost almost as much as the 01V96, so why waste your money?
This set up would cost, roughly:
HD24XR (XR has better convertors) - $2000?
Yamaha 01V96 - $2000 (add 16 channels of adat i/o - I don't remember $)
Motu 2408 with DP - $1400
Mac - $1000 (a two year-old dual G5 can run 48 tracks in DP without batting an eye.)
For this price, you could probably get a used PTHD setup, (minus the mixer, Mac, and HD24) but working with the HD24 is so easy, it's worth it just for workflow issues. It's just like having a 24 track machine, but you're recording onto a hard disk instead of tape. Plus, while your computer is on the fritz, or not on the fritz, but busy burning CD's or printing CD covers or whatever, you can still record.)
You'd still need some mics, and a headphone amp, but I think you'd come in under $8K. If you're more of a minimilist and don't need all the inputs on the HD24, or the mixer, you could just get the motu stuff, (one with built-in preamps, maybe) but be prepared to spend a lot of time with a mouse in your hand. And don't forget to back up your work to an external hard drive. (The HD24 comes with 2 drive bays, one for recording, one for more recording or backup. The first thing I do when I finish a session is backup to the second hard drive. And they're cheap, like $60 - $90.)
Forgot about monitors - Tascam VL-X5 - $300 a pair, I think.