Wolfgang - thanks for the pointer, and I like your mixer - nice work. Exactly the sort of thing I was hoping to see.
I've used the THAT 1200 series receivers before with very good results, and the price is right at Mouser, so your recommendation is a good one. I like the 2520 family DOAs as much as anyone and don't mind building them, but seems like a bit of overkill for the application, especially when you follow it with two or three stages of DOAs and iron, anyway. Another tempting input possibility is to take the Black Lion approach, and use a bunch of Edcor 10K/10K transformers for pretty cheap (~$12/ch) and really minimal work.
I already have a decent mixer (Malcolm Toft Trident-like thing), so I'm not ready to embark on something too full-blown, but it is tempting if the sonic results are worth the work. Actually, the ACA would be a much better summing bus for the Toft, but there isn't any room to mount it internally; I'd have to work out an outboard solution. My downfall is really metal work.
I kind of liked the use of simple LCR assignment switches to save money and panel real estate... I think one of the Dangerous boxes do that, don't they? On the other hand, it would be perfectly usable for my application to have dedicated R & L inputs, and do all my panning and levels in the DAW before the outboard summing. I'd likely also use the box to sum a bunch of old Ward Beck preamps I have, as well as some of Jeff's preamps. I sort of have a nasty mic pre fetish, and have far too many for my needs, including a bunch that I've done on perfboard and such over the years.
I'm torn about I/O connectors, though - I'm leaning toward XLRs, instead of going the DB25 route, although I guess I could just run DB25s from a patch panel and still have the same flexibility with the XLRs or TRS. I'll likely just prototype things with a stock XLR panel (like the ones from Middle Atlantic), without any metal work, and mount a power connector in one of the punchouts, instead of mouting a power supply inside.
I like Jeff's new VU meters - they are tempting to use for this, also.
Speaking of VUs, and only slightly off-topic: I'm trying to find which model VUs that Neve uses in their 8816 (I have a blank 8816 panel) - anyone have one you could peek at? I know that they are in a 27mm cutout, and that probably points toward Sifam (along with the fact that they are British and used elsewhere by Neve), but I haven't seen the same model as a stock offering.
Many thanks for the links.
Cheers, Frank