As it seems Matt has shown in a couple photos the other alternative to either bowtie or straight tie is a cravat that can be picked up in any tuxedo store and worn with wing color shirt in lieu of a bow tie, and I think it looks great as an in between, kind of like the Argyll being pressed into service as a more formal jacket and waistcoat where a PC might be considered more appropriate but not absolutely necessary.

I think the combo's that work from a tie and shirt standpoint are: Winged collar with bowtie (standard with PC, alternative with Argyll), Winged collar with cravat (dressy with Argyll, probably not appropriate with PC), winged or turned collar with Ruche tie (I know many will hiss at this option---semi-dressy with Argyll, no-no with PC), and turned collar with straight tie (standard with Argyll). If I am going with a bow tie I prefer a dress-front tuxedo shirt and a low cut (3 button PC style) vest, with the other ties I prefer the high cut 5 button Argyll style vest.

One man's opinion.