Hey again @DMartz I didn't want to keep you waiting on this any longer, so here are my thoughts around sending transactional/triggered sends to the Everest seeds.
Pros: Visibility on performance is the biggest one, IMHO. This is especially important if you're rolling out a new template or series (like a welcome) so you'll know what to expect.
Cons: Everest seeds don't engage with your emails, so consistently sending these types of messages to an audience where it's not opened can be detrimental in the long haul.
The great thing about transactional / triggered sends is that people are generally expecting this type of communication from your brand, so engagement should be high. It's a good idea to send them to the Everest seed lists periodically (1x a month / 1x a quarter) to keep an eye on them and certainly if you notice a decrease in customer engagement.
Hope that helps!