Definitely can’t go wrong with Atmos for organics, I don’t have as much experience here so I’ll talk about performance bi-metals instead.
Currently Asia is pushing bimetals the most right now, with some popular brands currently being c3yoyodesign, turning point, japan technology, yoyofriends, and also a lot of newer companies such as w!ld and sense (harder to get the newer companies over here in the states).
Some recent crowd favorites are the c3 Hydrogen crash, Turning Point Hinemosu, yoyofriends Nucleon. Turning Point bimetals are generally more focused on slower/methodical/technical play (look up players like Yuta Kashiwaya and Yuma Watanabe for some examples), while the other brands are making more ‘traditional’ bimetals (nimble, stable, long spintimes).
If you’re looking towards a North American company there are some excellent offerings over here too, the Banshee SS and Perpetual are both good (having thrown both I like the Perpetual slightly more), with some other crowd favorites over here being the CLYW Klondike, UNPRLD Nostalgia/Seiji, Duncan Grasshopper GTX 2, Yoyofactory Will, the list goes on.
Realistically I would find one you like the look of and go with that. It’ll be hard not to buy multiple, sorry 
. The bimetals I have in rotation currently are the yoyofriends graviton (great if you like wide/stable), turning point palpitation es (great if you want to go broke), and the Duncan GTR-JS (great performer, some find it slightly too heavy)
There’s some boutique stringmakers that do nylon such as String-Werx String-Werx Maker Thread