Possibly you'll get tripped up with the x86_64 packages, particularly when both x86_64 and i386 packages are installed. When the installer updates them I don't know if it will handle the change.
However if this is still on an x86_64 box it should run both kinds of packages fine.
Thanks for the follow up, will let you know if I get any hang ups, but since I posted this I have re-thought it, and I figure I"ll probably stick with x86_64 and just do more i386 packages where I need em.