I dont want to sound like a fanboy...Control4 comes in pricewise less than Crestron and I think usually less than or close to on par with Savant. Unlike Crestron/Savant it does come with 2 options to do your own programming. Composer Home Edition is software that lets you program anything 100% - the only drawback is you cannot add new hardware, you need a dealer. so yes, if you switch your TV (what, once every 5 years) you'll need a dealers help. Can it get tedious, sometimes but really how often are you adding things? I have a good relationship with my dealer and its a very minimal charge (if any) to just add hardware into the system. The other option is C4 just released "if when" which seems to be their answer to IFTTT logic type programming. It is a bit more basic than Composer HE with a bit less power but it is much easier for the common person to use. That said composer HE is not really rocket science and there is a helpful forum to learn even more.
composer HE is a 1x cost of $149. You need 4sight to use "if when" and that is $99/year but that also lets you get remote access to your house, Alexa services, push notifications and several other features.
You can likely cobble together multiple systems using ZWave and accomplish most tasks but like the above poster said, if something goes wrong or needs tinkering, it is all DIY. C4 is the closest big player to a quasi approach of some DIY with a dealer install system.
Someone posted about Alarm.com too and that can be DIY. Did you look into their home automation services?