New 75g Unplanted Cichlid Tank

I just bought a 75g and would like to try something different, also definitely want to have cichlids. Here's one idea I have -- thanks for any feedback you folk out there can provide:

Standard 75 Gallon
Filtration tbd, maybe 2 ACs or 1 AC & 1 Canister
Black sand, Rocks, Driftwood
No live plants (have those in my other tanks, want to try a tank w/o)

1 Severum, 1 Blue Acara, 1 Uaru (or some combination of large, more peaceful SA cichlids)
3 Silver Dollars
1 m/f pair of Kribensis rolleyes

I know that mixing cichlids is dubious, but here's my thinking:

Kribs and SA's have somewhat similar water requirements (I think), plus they would be from LFS so probably used to my local water.
I guess mated kribs can be fierce, but I wouldn't think two 4" kribs would do much more than try to chase away a few 8" sa's. On the other hand, I wouldn't think that the more "serene" sa's would care about a few tiny kribs hanging out at the bottom of the tank.

Not sure though, so please feel free to share any comments or suggestions.
Thanks!
Joel

^, Anyone have any feedback?

Thanks for the feedback. I do want to focus on CA/SA's, so if you could move this thread there for more responses, that would be great.

Thanks!

Saw some new juve sevs at my local petsmart -- looked great! Also, I'm losing interest in the silver dollars. So I think my new stocking plan is something like: Severum, Festivum(s), Uaru?, Kribs?, Some kind of catfish...

Here's the question part: Would this stock work in a 75g with black tahitian moon sand, driftwood, rocks, and no plants?

Resurrecting this thread now that I'm farther along on my prep (you can see the details in my blog if interested). Basically, at this point I have:

75 gallon, Play sand substrate, Quartz rock, *Huge* piece of driftwood (really psyched about this!), AC 110 and Rena XP3

Still want a severum, not really interested in schooling fish, "yes" interested in a mostly SA cichlid set-up (gt's, blue acaras, uaras, etc.), but want to try something "out-there" if workable. What about the following as possible tank-mates for a sev?

5 Pictus catfish
5 Yellow labs*
1 BN pleco
4 Angelfish (ok w/o plants?)

* (I know: not recommended, but I have this crazy feeling it might work)

Side note: Anyone know where I can find festivums? Don't seem available anywhere!

Thanks!