Hey, do you have any advice on how to make good features? I myself am fine, I just think some people don't get the idea. Some make very combat focused, and some people put things like ' you can do X very well.'. I think it's the hardest part, and I only realised that it should be this way a few months ago, and it would be so helpful. 

I think for backgrounds, combat-specific abilities should be avoided; anything important combat related should be determined by your class and maybe partly your race. Beyond that, all the official backgrounds seem to have non-combat features that I can see.

Background features are usually about stuff like getting free room and board, being better at forging, that kind of thing. Some background features can be super useful, others are just fun to play with, like the Pirate background (you can kick open every door you encounter with little or no consequence).

The common theme that seems to unite background features is that they encourage you as a player to do something, whether that's to seek out your guild for free lodgings (Guild Artisan), or to shun inns entirely and forage for food everywhere you go (Outlander).

Haravikk has pointed out some of the major points of background feature design. I want to emphasize that it should be a roleplaying or exploration feature and should have little to no mechanical effect. Sages don't get any mechanical benefit for knowing a lot (besides their proficiencies) but they know where they can find information. Nobles might not get advantage on Charisma checks when they invoke their nobility but that might create roleplaying opportunities.