This subject has become a major issue in Private League 75, which has several gms that have been playing for a long time and post extensively in both the league and this community forum.

The use of less than 4 or 5 plays on either defense or offense, intentionally, most likely results from those plays significantly standing out from the rest based on their average per play. As an example, given the choice of using a Cover 2 defense on 3rd & long that gives up an average of 8 yds versus a Double LB Blitz that yields 2 yds per play, there's an obvious advantage and many do not want to leave it up to the AI "Coach" to call the blitz. So, gms use rules to make specific defense calls, which can cause extreme results in the interface between several rules and the regular gameplan, with the use of 4 or 5 or less plays for the entire game.

Additionally, does play familiarity influence AI play selection? Very important to know this if it does.

Whether extremely limited play selection is intentional or not, I would like to suggest a penalty or control to curb it. Similar to when a team has too many players, for example, the AI steps in and cuts a player or sits a player (painfully one of the best) when the roster is above the allowed number. And, if a starter is played constantly, the fatigue factor comes into play and his ability/performance is decreased. I would think the same could be done for overuse of a play.
There is not much that can be done to balance play results so that the plays that tend to produce better results become more numerous and variable. With that in mind, like team rosters, you have your better players mixed with other of varying ability, which is all a part of the decision making process & strategy for a gm. It should be the same for the playbook and play selection, as you would have to use a mix of your best plays and others.

Here is the discussion thread on the subject from L75: https://private75.myfootballnow.com/forums/thread/1/215?page=2#1389

The current engine does have a penalty for reusing the same play but I didn't make it very high, I want to make sure I don't penalize legitimate play reusage too much. I will probably expand it and modify it in future releases.

If I'm reading that right, I'm definitely not in favor of any type of artificial solution to curbing play overuse, especially if it means the AI overriding your rules/gameplan.

1) What I am in favor of is the engine continuing to improve, which will hopefully solve some of the outstanding issues.

2) I am in favor of an increased 'player awareness' bonus when an opposing team runs the same play(s) over and over (but of course there's simple limitations to what this can even do until #1 is addressed).

3) And I am especially in favor of a reworking of the available plays. In my state of the game thread I highlighted the lack of "successful" plays as a major issue for the game's current incarnation. But again, I think this is also linked to #1, because as that changes presumably so will what works and what doesn't.

JDavid has said that he's working on a more complex and comprehensive testing method to evaluate that the code is producing the anticipated results. This should hopefully help him to understand why certain plays are duds and others dominant.

I would say that there are degrees of play overuse. And in the case of extreme overuse, which I have done unintentionally, it should be harshly penalized. Same as when I was penalized for having 47 on the active roster instead of 46, definitely unintentional, I just plain missed it, but it resulted in the AI sitting my most highly rated player for that game.

I support any adjustment or improvement that will motivate gms to select more plays to avoid a negative impact on play outcome. IMO, that will eliminate the problem and justifiable complaints about the use & advantages of doing so. Its a great game, no complaints, and jdb is doing a great job with it. This is just a suggestion that shouldnt be a difficult fix/adjustment to make it even better and address a problem that is creating a lot of discussion and concern. I dont mind varying my playbook and selection if I know its going to be a fair playing field and there is protection against abuse, whether its intentional or a mistake in the gameplanning.