I'll go ahead and comment that my first impression is that this would actually add complexity to the game at a time when we are trying to simplify it. At the same time I understand your point that it would remove the need for some specialized rules, and thus also simplify the game some.
However, the specialized rules only come up occasionally (and usually among very experienced players), while having a certain number of cards that you are allowed to play each turn would be something that EVERYONE would have to start keeping track of EVERY game. That is why I think the overall effect would be a more negative play experience.
Thanks for thinking outside the box though, and perhaps other elders will like this idea more than I do. Or perhaps after more thought, I'll come around to the idea. But I just wanted to share my first thoughts so you wouldn't think your idea was being ignored
