So now that I've spent some time listening to RuneAudio 0.3a and the TPA3116, what do I think?
The best amp I've ever heard (with home usage in mind, none of these will be able to play at stadium volume levels) is the Topping TP20 (a T-amp using TriPath's TA2020), and I've both heard and had quite a few amps. This is definitely in the same league as the TriPath. Using the TPA with lower volumes, it's clearly better.
The sound signature in RuneAudio is a very important feature for me. With the TA2020, I found that the default "RuneAudio" profile was the best. Now, with the new amp, the "ACX" profile gives me the same transparency.
I've got a 19V/3.5A power supply for the TPA3116, I guess that would bring me in around the 25W territory. Compare that to the TA2020, which would provide a maximum of 8 clean watts into my 8 ohm speakers. In terms of absolute volume, the difference is almost non-existent.
I can't declare a winner, but it's nice to know that there is an alternative to the TriPaths. ThriPath went bankrupt more than five years ago, and the supply of amplifier chips must run out sooner or later.
I'm happy with my build and the amp sounds great. The versatility with more inputs, balance control and (when it's complete) a phono preamp is sufficient for me to keep it as my main amp.