Control4.

One remote that fits all projects. Single room TV, yup $600.
Multiroom project, bigger processor, but same remote.

Tech support calls, my guys know which remote they have.

Minor tweaks, sure, we can do that for you from the office.
AA batteries, yup got those.
Want rechargeable instead, no problem, it's done as an add on kit, same remote.
Dog ate the remote, I'll send you a new one, call me when it arrives and we'll commission it. (oh, and it's only $200, not $600 or more)
Different SKUs to stock, nope.
Durable, yup.
Fully customizable, nope. But from a client perspective, that hasn't been an issue, for MOST clients it all they need, I'm not saying it's for everyone, but for most.
Reliable RF, you betcha.
RF repeaters if necessary, sure
Expandable, tons. Lights, HVAC, Cameras, Sensors
IP Control, we got that too.
RS232, yup, and even a check box for a null modem cable setup in programming.
HUGE device library, yes, and it's free (there are some 3rd party drivers that cost)
App to troubleshoot, yup. ("My range doesn't seem the same", open app, you're battery is at 8%, dude).
Lesson Time - press "Watch" select the source you want to view.
Includes streaming music services too; Pandora, Rhapsody, Tune In, Tidal, MP3, Wave, AIFF, FLAC!
On screen gui - very cool, but not required
Sonos support - oh yeah
Smart phone / tablet app - FREE
Client control from offsite - yearly fee (someone's got to pay for the VPN servers)
Apple Airplay - included
Software updates and improvements - regularly, free for the most part.
Easy to order - yup
Sold in distribution - NOPE
Support for older equipment - as much as the older stuff can handle.

Lets do a standard family room: Sony TV, Sony Blu-ray, Sonos Playbar, Apple TV and a Set top box. That's one emitter (assuming it's a cable box, cause satellite is also IP), the rest are IP. Once the network setup and Sonos setup work is done, you can program this system in 30 minutes. (oh and since the Sonos is IP, there's no TV vendor stupid volume bar on screen that doesn't match the level of the Soundbar to explain either)

Oh and to repeat, all that for $600 retail for a processor and remote, batteries are included.