"Maybe I will keep the LA4 and switch back and forth."
Great choice. Get another preamp for variety. If your power amp has a front facing switch to toggle between RCA and XLR inputs, then you can even have 2 preamps hooked up at the same time. You need to see if your Bricasti is good with having the RCA and XLR outputs connected at the same time to 2 different preamps. In my office, I have my Yggi+ OG DAC connected to 2 preamps and a tube headphone amp at the same time.
BTW - My Schitt Yggi+ OG was compared this weekend to the Dave and the Tambaqui at a pretty cool headphone event. I was not there but I got feedback that both DACs were slightly favored over the OG.
"The LA4 does a better job with the M1S2 than the DAC does by itself."
I found that all DACs I had in my system were better served by the volume on the LA4. The only one that came close was the Lumin X1 that has a special Leedh volume control. Even that had a slight gremlin at the lowest volume levels.