I wouldn't do more than a pair of speakers in each room.
The family room should be setup as an audio/video zone with a surround receiver, not a stereo zone. 5.1 or 7.1 at the most. The room is NOT ideal for surround sound, so perhaps even 3.1 may be best.
Stereo speakers in the kitchen to match the left/right of the family room and the ability to play back the same TV shows.
Stereo in the dining room and living room. Two speakers per room.
Depends on what you are doing in the bedroom, but we went stereo, with speakers flaking the TV on either side.
All our bedroom are the same with stereo speakers flanking the TV location.
The speakers I linked to will provide ear bleeding levels of audio just fine. You do NOT need more speakers in these rooms.
Secondary rooms, such as bathrooms or laundry rooms can use a single stereo speaker to fill the space nicely.
Using more than a stereo channel of any amplifier is really not appropriate in these spaces based upon your home size. For reference, my home is about 4,000 square feet on the main two levels so I'm familiar with how this sounds after it is setup using the speakers I've recommended.
As for whether you get your money out of this type of setup or not is not really a question. You get whatever value you get from your use of it. We certainly didn't use the speakers that often in rooms that we didn't use, but I LOVED having speakers in the garage and outdoors when I was doing yard work or working on the car. I liked having them throughout the house when I went through on cleaning days or during parties.
As for reliability - in the 7 years (!!!) that I owned my last home, I had ZERO issues. No amplifier failure, no keypad failure, no panel failure, no component failure. If Russound has amp reliability issues then avoid them. Sonance, Speakercraft, and Niles all make very reliable long term use amplifiers. Keep an eye on eBay as I know the 12 channel, 30 watt per channel amps show up for under $500 quite often.
A couple are up there now...
Sonance Sonamp 1230 - 12 Channel 6 Rooms or Zones with Multiple Configurations | eBay
It is very important, that you pick a VERY well ventilated area for this equipment as heat will devestate amps and other gear quickly if it is sitting in a closet somewhere.