Help balancing speakers / dynaudio S1.4 & receiver vs. pre/amp

[gileas]

I am upgrading my home audio / theater system.
I have purchased a pair of Dynaudio S 1.4s at a good price - 800$ for the pair. Now Im thinking of using these for the front left & right channels. I have infinity reference speakers for front & rear & center atm, driven by a Denon AVR 2400. I am looking for help with two items.
1) assuming I do not buy the dynaudio 'matching' center and rear speakers, can I get away with using my Infinity for rear and using the infinity center for a while, until I can find a good center?
2) new receiver. I have a Rotel 1056, but have the option of taking it back and getting rotel seperates, or Krell, Marantz, burmester, or a few other mid-high end receivers or seperates. I have 1300.00 in on the rotel, and can go another 700, or so.

The store sells the following (I have a $1300 credit with them and can spend maybe another grand at most) B&W, Benz Micro,Billy Bags, Burmester, Chief Manufacturing, Crestron, dCS ,Dynaudio,Faroudja
Finite Elemente, Fujitsu Plasmavision, Grado, Graham Engineering
Koetsu, Krell, Loewe Video, Lyra, Magnum Dynalab, Marantz
Meridian, Musical Fidelity, Nitty Gritty, Premiere Seating, Quadraspire
Rega, REL, Rotel, Russound, Salamander, Stewart Filmscreen
Sumiko, T+A, Tara Labs, Vidikron

Cables - these guys are way pushing Tara. Im happy with my monster. Comments appreciated all around.

Oh I can get a nice pair of Snell Type KIII for 100 a pair. Thoughts?
Thanks,
Gileas