Somehow HDMI audio is still less convenient for me.
I send HDMI to my TV which sends optical to my sound system, and it still works pretty well. Earlier this year I bought a nice sound system with a receiver for the reasons you mentioned, but it added extra lag to my video games, so I returned it. My current sound system also supports ARC but it causes most of the same problems. Decoding those fancy codecs creates lag on every system I've tried, so sticking to LPCM over optical seems to be the only way to enjoy games still.
I send HDMI to my TV which sends optical to my sound system, and it still works pretty well. Earlier this year I bought a nice sound system with a receiver for the reasons you mentioned, but it added extra lag to my video games, so I returned it. My current sound system also supports ARC but it causes most of the same problems. Decoding those fancy codecs creates lag on every system I've tried, so sticking to LPCM over optical seems to be the only way to enjoy games still.