No single instance has very "broad" POVs, however some instances are federated more broadly and thus get more points of view. To that end, Lemm.ee and Lemmy.ml are much more diverse than Lemmy.world, which is defederated from the major instances with large populations of Marxists.
Hexbear and Grad tend to have a lot of Marxist (and Anarchist, in the case of Hexbear) perspectives you aren't really seeing much of on Lemmy.world, which is very "US Democrat Liberal."
You aren't going to find anywhere where the virtue of being "different" is worthy of celebration when it comes to POVs, and I think that's a bit of a lost cause. I don't see much value in entertaining the opinions of fascists, as an example.