First off, I really recommend you consider brooding outdoors instead. Makes for less work for you, easier integration, and is more "natural" to being a chicken except for the fact that there's no hen. Enrichment isn't an issue for me.
https://www.backyardchickens.com/articles/short-on-time-recycle-a-prefab-brooder.73985/
1/2 sq ft to start is fine but by 6 weeks-ish, I'd say 1.5-2 sq ft at a
minimum.
Yes you can have too much space in a brooder, when they're very young (i.e. less than 1 week) chicks could potentially get lost in a large space and be unable to get to heat or water. But too little space can cause behavioral issues, such as chicks pecking each other. I give them over 2 sq ft from the start... by 2-3 weeks they're already insane and want to be outside.
No chicks don't need roosts in the brooder. You can put them in for enrichment, but it doesn't necessarily mean they'll learn to roost faster.
Shavings are fine.
I have no way of hanging a feeder or waterer so no opinion on that.
I prefer a mama heating pad over the options you listed but that's because I could make it for $2, and heat lamps make me worry about fires.
That's not how a heat plate/pad works. It does NOT warm the air, it works by direct contact. Chicks press against it to warm up, and then leave when they don't want it.
I personally feel the lid you're referring too is inadequate in ventilation. If you must use a bin (I recommend against it) then I'd cut open the majority of the center of the lid and securely attaching hardware cloth to cover the hole. More "windows" can be cut into the side of the bin if you want.