A few suggestions:
1. Please add a right-click menu item of "Paste Artist Picture" that will overwrite the corresponding dat file in ArtistCache folder with a copied picture. This will also help to address not-properly-clipped pictures by manually replacing it.
2. Ability to move artwork to the right side by dragging it, just as another (right-aligned) layout option.
3. Option to choose the blending color either from artist picture or from artwork (as with Bee-liever's wish).
I like 1 and 3. but I am nut sure I understand option 2 (I know they are not directed to me, but just curious), is it a function we can do in other forms of musicbee already?)
for #3. I also like Bee-liever's suggestion, but as Redwing suggested, would also like the other option.
for #1 I agree as I still would not want this to become a second theatermode in a sense... because as Redwing has demonstrated, we can achieve some of these things in a theatermode window.
The way I see theatermode, is that it is not something where you are expected to do much (unless customized to do so) but instead, a display of sorts for entertainment/appearances value.
Compact player I feel is a more active window that you would use in place of the regular player window for the sake of size and I guess convenience... well, same thing as the classic compact player, though some degree of reduced function is expected to accommodate what we are striving for. So.... a click-able interface similar to the current compact player, but just more eye candy.
Again, I realize that the same functionality cannot be expected, but hoping to maintain some degree of it.
I hope I made some sort of sense there.

They are not lazy... just more efficient.