im not totally sure what you want.. but i guess there is a way to do that..
under the album artist thumbnail you get var because when there are more albums the value varies.
to get around this you could use numbers, because under a thumbnail mc will write the average (not for all values, some are treated different).
now you could make a new library field, give it a name (like CalcHires) and make it a calculated field. as the expression for the field use something like this
if(isequal([Album], -24], 8), 100, 1)&datatype=[integer]
now test by putting [CalcHires] under the thumbnail..
it schould 1 when there is no hires album under an artist and something else when there is.
now under the thumbnail use
if(isequal([CalcHires], 1, 5), <font color="0000FF">[Album Artist (auto)] <//font>,<font color="000000">[Album Artist (auto)] <//font>)
i did not test this totally, because i dont tag my files that way.. just thought it could work..
gab
edit: changed it a bit, because 0 is not always working well, and i made it the wrong way around... hope this does it..