Maybe add a rode videomic pro since that's a very good high end professional mic.
No, it's not a "very good high end professional mic", it's a consumer toy. Where are you getting your information?
Not paying £1000-£1,500 for a microphone! Or £1000+ for a recorder. Just a waste of money when I have this equipment to do the same job. Will get GH5 and Canon 5d mark iii used.
Why do you need two more cameras?
And getting quality equipment is not a waste of money. Ten years from now a quality microphone will retain a very substantial portion of its resale value. I can still get 40% to 60% of the original purchase price for most of my mics, many of which are 10 to 30 years old and still sound great. Can you say the same for a camera? The same goes for a quality mixer/recorder. There are plenty of PSMs out there who are using 20 year old Sound Devices mixers that still sound terrific. How many DPs are still using 20 year old cameras? This is smart purchasing, not wasting money; a substantial ROI (Return On Investment). Ten years from now you can take most of the gear that you bought and toss it in the trash can. How is that a smart investment?
As AcousticAl pointed out, you are shortchanging
HALF of your production values. What you should really be doing, if you really want to be a professional filmmaker, is not buy anything, but renting what you need on a per project basis. Can you name one prominent director who owns any gear? They rely on their department heads to procure the proper equipment for the project.
My specialty is audio post. I have a decent mic collection and the rest of my gear is very solid for a "budget" studio. When I need to go into the field to record sound effects I rent what I need. And guess what? It's always far better than a prosumer piece of gear I would have purchased. As a mentor taught me, "If you don't use it every day, you don't need to own it."
Just for fun, the Rode NTG-3, (which the professional production sound people refer to as "the poor mans Sennheiser MKH-416") is only $700. And the Sound Devices MixPre-3 is only $550. That's what I meant about doing your research. You can get quality entry level pro gear at very reasonable prices these days.
Sorry to be so brutal about this, but the entertainment industry is a brutal business.