It's not overkill, you just may need to consider the placement of each speaker, within each room. If the in-ceiling speakers will double as TV and distributed audio speakers, they should be placed closer to the TV, equidistant to the main viewing/listening area.
I wouldn't put TVs above fireplaces, but some people love that.
Will a TV be installed in every marked location, immediately? If not, then bring the cables to outlet height, with plenty of slack. Power can be extended to TV height at a later time as well.
Speakers in balcony ceilings, if they're covered.
Remember DVC/single speakers are supplied by 14/4, as mentioned above. Each regular speaker would be supplied by 2 conductors each.
Might want to consider an alarm system. Phone system can double as a paging system. Any exterior gates will need cabling to 1 or more locations in the house.
Is laundry room large enough to accommodate the equipment? Laundry room may need a fan, for the additional heat from amps. You'll need a good deal of space for the amps and other control equipment.
Some areas may benefit from 8" in-ceiling speakers - sound is a little better. I would put a stereo pair of speakers in the garage, rather than 3 DVC speakers. Single stereo pair above the island may also sound better than the 4. Same with the breakfast area.
Trellis area may benefit from a speaker, or 2, if you plan of using that area to entertain.
Yard, pool, and outdoor kitchen will need sound. Conduit will be used to extend low voltage to the outdoor kitchen (from somewhere), plan accordingly.
Wire for automated/electric shades/drapes, especially for tall windows. I love my electric shade in front of the kitchen sink.
Family room may need a couple subwoofer locations cabled (coax cable). Or, position one or more subwoofers in the ceiling. Where else would you want a subwoofer?
Vacusweep/Cansweep are much, much better than Vacpan. You need one in the kitchen. Very easy to sweep, hard to get out the vac hose.
Our vac hose hangs on a wall of the laundry room closet, off the kitchen. Consider the 40 foot hose (standard is 30').
Water sensors may be useful, to turn off a water main valve in the event of a flood (2nd floor laundry room).
Consider control for the exterior lighting. Banks of switches at the front and back doors (and kitchen sink)? Or a better solution?
Natural gas to the grill? App control or automation of the gas fireplaces?
Considered lighting control?
HDMI isn't a good option to run to each TV, because of distance limitations. Try to keep the sources local (small cable client box and/or Roku hanging behind each wall-mount TV).
If you don't have a lot of experience, you should hire someone for guidance. Most builders are great at building, but hit or miss for AV details. They can't be good at everything.