I haven't stress tested this for '24 yet, but based on my experience on previous versions, I don't feel that low tactical familiarity is terribly detrimental to most teams. And I say that with having played systems with 30+ tactics that I would regularly cycle between.
The most effected players are typically your high mentals, low athleticism/technical players. This is because the penalty, at least in previous versions, largely just applied to mental attributes. Your hyper athletic winger doesn't run slower because of low tactical familiarity, but your midfield playmaker may find his lowered anticipation and decisions has him out of position more often and if he is unathletic on top of it, can struggle to recover.
One of the best ways I have found to mitigate this is basically set up a primary default tactic as normal. Then use the other two tactics to basically set up tactics that represent the trainings for any other variations you play. For example, if your default tactic is Positive mentality, but you want to be able to push mentality up and down, while minimizing the effect on tactical familiarity, then have the other two tactics be balanced and attacking respectively. Similarly if you have a wide player that you typically play as a Winger, but like to bring inside occasionally, have a formation/role in the 2 training formations that reflect that change.
Note: These training tactics don't need to viable or used in a match. They just represent the bookends and various variations you might introduce at some point.
This typically isn't enough to keep you at 100% familiarity as you make changes, but you will find that you can make a lot of changes and still be like 85%+ familiarity with the final product.
See these posts for more detail on how you can set up training formations to cover a large swath of options for use in match:
Note that these are older versions of the game, but I played a similar system in '21 without issue and I haven't seen any glaring issues yet in '24, though admittedly I haven't gone too deep into the new version yet to confirm.