Console Output Channels

We've created an automated method for generating equivalent virtualized system images (Amazon Machine Images, VMware and Azure templates, etc.). However, it seems like specifying the same console= element within the GRUB(2) config (e.g., ttyS0) does not seem to result in the same output in the various environments. Basically, we'd like all boot messages to show up on the RHEL7 instance-console ...and for all of the VCs to be deactivated (since they're not even reachable within an AWS context). Is there a "one ring" kind of console= setting that can be placed in GRUB(2)'s kernel line to ensure uniform, verbose output regardless of an instance's launch-context?