Well, a real life offense is going to keep doing what works too. How much variation was there when the Ravens ran on the Pats 52 times (46 if you take out Flacco's runs) in their game? Or when the Ravens said "Screw it, we're running in down your throat" the whole second half of their game vs the Raiders?
Heck, the Pats game, they got 234 yds (229 if you take out Flacco's) - so just around 5 ypc - and they kept going it. So it was effective, and kept doing it. A Madden playcaller should have that option - just that Madden needs more run plays that work so I wouldn't have to call 30 Power O's with flips to be just as effective as my real life Ravens.
I'm willing to guess a lot of the variation is more with packages or subtle changes. For example, one pass play might be 4 WR - all Go routes. Then another might be 4 WR, Go's outside, and a slant in one slot and a curl in the other. Then 4 WR with Three Go routes and a quick hit drag in case it's a blitz, etc.
Then another play might be 2 WR, the HB and a TE - all running Go route except the HB is running the slant and the TE running the curl.
Same for runs. One might be strong I - A gap HB Dive. Then same thing, but B gap. Then same thing but Off Tackle. In Madden - we just have "HB Dive". Yeah.
Until we get that kind of variation, I think we can't limit anything. I'd rather EA just make all the plays be effective so the temptation isn't even there because you know only about 15-20 of the plays are truly effective in any one book.