Qs re Video Mixers, Streaming, Cameras, and the Roland VR-1HD

[BlinkyLights]

(New to video synthesis, am ignorant to much if it still, just now starting to dig in and learn. forgive my basic Qs...).

So - I already walk around with a sense that I know I want a video setup, I simply haven't gotten to it yet, time and $, and competing priorities, all that. But soon, I've been thinking for months now.

Anyway, yesterday I saw a demo video for the Roland VR-1HD:



There is much I like about this box. Easy hands-on mixing of 3+ video sources, sound (or midi or cv?) synced camera changes, integrated streaming codec/setup, small / portable, cheap-ish.

But, I suspect there are many ways and gear combos to achieve (basically, at least) what this Roland box is doing, right?

Something like (made up example): "sure, the XYZ Mixer with an ABC Streaming Box and one of those 123 effects boxes, all chained together, is even cooler, for even less money..." or whatever... right?

What are all/most of *those* things/combos ^^, alternatives to the Roland box, especially alternatives where the further integration of crazy FX is easier? Something that facilitates boring stuff and crazy shit?

What's even cooler than this Roland box, "just" for these Mixing and Camera and Sound features ? (not the crazy effects parts, I realize those require other modules). But what about basic 3-8x camera setups for pod/broadcast or just live performance recording of multiple angles, as well as for live performance video wall fx and such, something that can adapt to eitherof those scenarios?

How do you all do these things?

Also, talk me through Cameras, please. To what degree can I repurpose old phones and misc cheap b.s.? What are the cheap but okay new cameras? How much do the "good" or "real" cameras cost, for basic ones good enough for home/club/outdoor/small stage use?

Thanks.