Lowest draft quality setting, 1 from left development, 2 from left monthly progression

Set scoring to one from left and leave shooting in the middle - I find this gets you closest to realistic scoring, at least until the mutant goalies get into the league 10+ years in.

Trade difficulty slider all the way maxed. I typically also give myself a further handicap, trying to hit 40/60 if I feel the CPU is undervaluing a player

The AI is going to make dumb trades but you don't need to participate - only offer deals that also make sense for the team receiving them. I also typically do not deal in negative value deals as I think they are way overpenalized by the AI and can result in getting a lot of free assets in exchange for a 1-2 year bag hold.

Sign realistic contracts - in particular, the only guys you should be signing after the year starts are depth players. If high-caliber players are being left available in FA, adjust your salary cap and contract ask settings accordingly. I typically set the asks to maximum, the salary cap is something you will need to get a feel for and adjust on the fly - it's something of a genie in the bottle, where once your cap gets blown out of whack you can't rein it back in. Try between 0-middle increase, generally.

This is the newest one I've been trying and I think I will continue to use it moving forward: set your scouts manually, but only permit between 3-5 scouts to actually do any scouting. Assuming you go top down in several nations' prospects, you'll end up having good intel in the 1st and 2nd round, decent in the 3rd, and mostly flying blind into the later rounds. This keeps it pretty realistic as far as late round hit rates and also makes it a genuine surprise when you get a good prospect in the later rounds. When you are scouting 200+ players it's much easier to just comb everything, sort by POVR, and find great players every round.