Plastering brick fireplace

Any advice on plastering this? I talked to a local professional who was kind enough to offer some guidance. He said plasterweld, structolite for scratch and brown coat. I'm thinking of using Firmolux Marmorino Piatto as my finishing.

Am I missing anything? I have about 50 sq ft of brick on my kitchen island that we will be removing anyways so going to work on that first.

How thick will this end up being? Trying to know if I need to extend the TV mount, cleat for the mantle etc.