New to the Group & I need your Suggestions

[Centofanti]

I am new to the group living in Surprise, Arizona (attached to Phoenix). I am almost a new Sony onwer leaving Canon after 20 years and here is my question:

As a long-time Canon user, I am tired of the lack of a fast 300-600mm lens option that doesn't cost over $11k. Since photography is just a hobby for me, that price point is out of the question.
Because of this, I’m planning to trade in my Canon R5, my 70-200mm f/2.8, and the 100-500mm f/7.1 (which I honestly can't stand because of the slow aperture at the long end).
Here is the Sony setup I am thinking about switching to:

• Sony A7R V (or A7R VI if available) - This is my absolute max budget for the body.
• Sony FE 70-200mm f/2.8 GM OSS II
• Sony FE 400mm f/4.5 (paired with a 1.4x or 2.0x teleconverter to get that 600mm reach)

For context on what I shoot: I do not shoot birds. Instead, I focus on large animals in national parks and zoos, as well as Air Force fighter jets taking off and landing directly overhead.
What do the Sony experts here think of this transition? Does this kit make sense for my shooting style, or would you suggest a different lens combination?