You don't want to manage five suppliers, three quotes, and a chain of people who blame each other when something slips. You want to talk to one person who actually knows your business, and have the right specialists turn up when they're needed.
That's the model. I sit at the front. Everything runs through Cardboard Creative, the studio I've been operating from for years. Podcast Foundry handles podcasting. Trusted partners handle video, photography, web and digital. Everything is briefed by me, sequenced by me, and reports back to me.