It depends what you're looking for, honestly. The "House Rules" thread is long, but an excellent read. It's a great thread of how people have added realism, and made the game more challenging for themselves. The self imposed rules range from injuries, recruiting, coaching style, playbooks, playcalling etc.
https://forums.operationsports.com/f...ule-ideas.html
If challenge is a key, a lot of people turn off fatigue and don't use any coaching perks. There's a lot of ways to tailor the game to your own skill level though, as you'll see in house rules.
A big factor for me is using the sliders too.
Also, here's a thread of people's custom conferences. Personally, I like to follow the real life conferences, for the most part. Some people do promotion and relegation too.
https://forums.operationsports.com/f...nce-setup.html
I hope this helps!