It sounds like you are looking for a way to play your whole library or something similar. The method you described is one way to do that.
You might also enjoy Play Doctor. PD plays similar songs and albums based on what you seed it with. Play Doctor appears when Playing Now is empty. Or you can choose it from the right click menu, similar to what you described.
Now about the new Shuffle Albums feature:
JRiver MC has several ways of shuffling songs. There's shuffle mode. There's also "reshuffle". Shuffle Mode keeps shuffling things and puts a check mark next to it, to indicate that mode is on.
But "reshuffle" is not a mode. It's a command. It tells MC to "reshuffle" all songs in Playing Now. Mix them up randomly. This is actually really nice. You can add a handful of albums and choose reshuffle and all of the songs are randomized.
So what is "shuffle albums"? It's very similar to reshuffle. It randomizes Playing Now, one time when you select it. But it keeps albums together and their tracks in order. So it shuffles playing now, but by album, not by individual song.
I hope this helps.
Brian.