You can do what we do- use LMCE to host the Squeezebox server, but then use the free Logitech Squeezebox app to control the audio for the 3rd party plugins. I haven't tried Pandora, but Sirius XM works great. Big kicker is LMCE doesn't know something anything is playing on the devices, so this is a band-aid and not an integrated solution.
Biggest problem we had was Sirius was coming in as WMA (iirc) and if you look online there are a whole lot of steps to getting it to work- or there used to be. Turns out there's now a 3rd party WMA plugin available through Squeezebox that fixes all of this. I don't remember the steps off hand- if you log into the server on port 9000 there is a way to show the available 3rd party plugins and in that list will be WMA. Again, can't remember if that was the format or if you'd even have a problem using Pandora.