Here is what I do and I strongly recommend the same. it requires NO compromise for 2 channel sound and fully supports your HT.
1. Design and build your 2 channel system. the only thing you need to make sure you have is a second analog input. This input will be used for HT. I have an amp with 2 inputs.
2. Design and build your HT system. Make it 7.1 or 7.2. at least 5.1. you must have a center speaker. Make sure your system has a preamp level output for your front speakers. Run pre-out from your HT preamp or HT receiver to your 2 channel amp/preamp/DAC (my DAC has an Analog in to make it more flexible) and attach to your second set of inputs.
now when you’re ready to listen to HT you just switch your amp (or your preamp if that is how you do it) to the input that your HT is set on.
You will have to adjust your sound levels if you use a preamp. I don’t recommend turning it all the way up since you will eventually forget to turn it back down. I suggest turning it to an arbitrary but very loud setting such as 1200 or 300--some setting that if you forget to turn it back won’t blow a tweeter. Then go through your HT set up program and let it set the level for the front speakers.
Jerry