Alright,
I'll have to make a video this week haha. Few years back when i was still in college me and one of my roommates played daily. We beat the PC by 100+ shut outs before and my personal best was a 70-80 point shut out versus a PC 1v1. I'm definitely not as good as I use to be but I figure I have to be one of the better players around haha.
Here is a demo I did for the NFL BLitz 2015 MOD:
https://www.youtube.com/watch?v=ehf2zlWBPJAAs you can see in the video, pretty much use turbo with your QB and jump to get more time in the backfield. Da Bomb is probably the best play versus PC also. The middle receiver generally can get enough separation the first few scores to score on one or two plays. Another thing with Da Bomb is if you run to the left your able to have the option to run the ball or throw it if a receiver gets open. I probably use about only 3-5 plays in NFL Blitz... I'll make a video with each one showing how I use them.
For defense a lot of people will either blitz the middle or line up with a receiver and knock them down right when the ball is snapped then change players and tackle the QB.
But yeah I'll make a video showing a few good tips.