My possible interest in a programmable Harmony remote is not aimed at PP presentations. It's mainly for simplifying a multi-remote AV scenario for non-technical members of the family, i.e. everyone but me
This was my goal, and has been a huge success for my family. I do have a fairly "simple" (or complex, depending on how you look at it) Home Theater setup, though.
My receiver is hooked up to precisely
one device: the HTPC. It has no cable box, no BluRay player, no game console, no other input devices connected of any kind.* On the Logitech remote, I have the central "TV" mode-button set up to turn the TV and Receiver on and make sure they're on the right inputs (to thwart any manual button-pressing guest-monsters), send a "wake" command to the PC, and activate the HTPC "button layout". Many of the buttons just do their keyboard equivalent via Bluetooth: U/D/L/R, OK (enter), Vol Up/Down, Back (esc), number pad buttons, play controls (except record which is MCE and handled by Girder). The rest are mapped to MCE IR codes, which I then catch in Girder and use to run context-determined macros and VB scripts.
The DVR button launches MC in Theater View, or does the equivalent of F11 if MC is already running. Guide launches the full-screen/tablet version of the Windows 10 start button, from which I can launch other applications if needed. In most applications, Info does the Keyboard Menu button, though this varies from application to application.
My wife occasionally still has trouble with it, but that's because Girder seems to "hate her" and always picks when she's trying to use it alone to crash. (I should really replace girder with Eventghost, but I'm lazy-busy.) My daughter, now 9, has known how to use the setup without help since she was 3 1/2.
* In fact, it drives me kinda crazy the price I paid for the Receiver, considering it is a glorified power amp (that always stays at the same volume level) and HDMI decoder. Since MC does all of the audio decoding, it doesn't even have to do that. I just send it 8 channels of PCM over HDMI. I used to play around with Bitstreaming but letting MC decode everything is less fiddly and "just works" (and I like its "night mode" better than the receiver's).
But it is nice and it does the job. The "music" mode-button on the Logitech is set to activate the Receiver's "AirPlay" mode, but I almost never use that. The "movie mode" button used to switch it to my old Gen3 AppleTV, but we never used it, and one day the AppleTV died and I didn't replace it, so it now does nothing. I don't have any smart lights or anything, and my remote is the older version that lacks those controls, but if I ever get something I might use them on the new one to set the "mood lighting" in the living room.