A bridge can support up to 50 light bulbs, so you are pretty much able to control every light in the house unless your house is as big as the White House.
This approach would not work if your internet service provider had an outage. Apps that communicate directly with the bridge would be fine so long as the local network is up, even if the broader internet was down temporarily.
Meet Hue app provides one simple preset for dawn and dusk, both just ramp up the brightness to one color with no intermediary colors/brightness like a real dawn or dusk would.
A handy feature that is missing from the official Philips app is the ability to group several lightbulbs together. This way you can adjust the color and brightness of several lights at once.
The application has no keyboard shortcuts making it difficult to script or schedule lights using the Mac as a server. This app is best used with a mouse.
If you want uniform colors among several bulbs of different generations, Colors for Hue does a great job of making them look similar. For some reason other apps don't do this as well as Color for Hue.
The first option in the menu is a toggle between Turn all lights on/off. Sometimes Colors for Hue doesn't detect that the lights are off, so you see the option to turn them off, but not to turn them on. Refreshing doesn't resolve the problem. It a simple matter to use the brightness slider to turn on the lights. This is a small bit of a quirk in usability.
This application doesn't do any scheduling, it makes live adjustments over the network throughout the day. So for it to work your computer should ideally be on, connected to the network the Phillips Hue is on, and not sleeping at all times.
Other dawn/dusk simulators change color in addition to brightness which more accurately simulates dawn/dusk. There are no options to pick color sequences for dawn or dusk.
The options available is the duration of the dawn/dusk routine, what time the routine should start, and there is a toggle to set the time automatically based on your geographic location and local dawn/dusk times.
With listening mode enabled, this app can trigger a preset, then revert to the prior mode after a specified amount of time has elapsed. This was intended to be a security feature. The idea is if someone broke into your house or something and they approached your computer or wherever your microphone is, Hue-topia would register the sound and trigger hue lights of your choosing, and this might be enough to scare them away.
This feature could be used in unintended (hacky) ways as well such as with a virtual audio device such as Loopback. It's a simple feature, it's only good for triggering one preset temporarily and then reverting to the current settings. It can't do Home Kit/Siri kind of stuff.
You can assign function keys 1-8 to trigger presets. You can also turn all lights off (but not on, however you can get around that with the presets + fn keys) and a few other misc keyboard shortcuts.
This means the application must be open (in the dock) for the menubar to exist. If you close the application from the dock or Quit by shortcut Command + Q etc, the menubar and FN key shortcuts disappear AFAIK. Scheduled items should theoretically still work. Will contact devs and do some more testing before purchasing.
Color picking in Hue-topia is not as user-friendly as other offerings. You can't click and drag your eyedropper. Wherever you click, that is the spot sample of color that is sampled.
The same applies for using the MacOS built-in color pickers. Sliders don't slide smoothly, they can only jump so much at a time.
Some of the APIs are command line friendly. There was a Bash API on the list. It might be very easy to pick up and use. It could be a fun project to learn how to design an application that uses a ncurses interface.
Make what you want with less sweat equity than starting completely from scratch. The frameworks are there, it's a matter of learning them and building with them.