Necklace for men: chai or Star of David?

I’ve been wanting to get a necklace for a while now. I’m a bit torn on a few things.

I read somewhere on here that a lot of men seem to go with chai. Overall, I see Star of David far more frequently (mostly women though). Any opinions?

I’m struggling to find one that is more “masculine” looking if that makes sense. Not too big or dainty (no bigger than a nickel). No flare. Looking for something simple.

Also curious what metal people choose. Gold, silver, stainless steel? I am trying to keep it on the cheaper side for my first one, FYI.

Finally, for guy, what length is ideal? I’m leaning towards 20-22.

Would appreciate any examples or opinions. Maybe I’m being too particular, but I’m not familiar with men’s jewelry whatsoever.