Hello Scott,

this is something possible.

you can implement a primary/backup strategy or you can have some VRF sites using CE1 as exit point to internet and other sites using CE2 as exit point to internet.

to implement a primary/backup you can increase the local preference on vpnv4 update out PE1 connected to CE1 (let's suppose it is primary).

otherwise IGP metric to PE1 or PE2 should decide what default route is installed on each VRF site. (point of view on SP IGP of PE node serving the VRF site)

Depending on the PE-CE routing protocol in use there can be other possibilities (like extended commnunity to carry EIGRP cost for example)

Hope to help

Giuseppe