Worse thing is, the game IS balanced for some cases.
So this "fix" has more potential of disaster than no fix at all.
For example if the chars that should take those feats/items don't take them, and those that shouldn't take those feats/items, take them.
As you already pointed out.
Actually, I only dislike the NAD feat and item fixes. +9 more to Will than possible with original core rules with two items and a feat is ludicrous.
The Expertise fix, I think, is fine, even good, because it does two things:
1) Keep "to hits" for PCs closer to monster defenses.
2) Speeds up high level combat which is fairly slow due to increasingly higher number of higher level monster hit points (which outstrip dpr increases by quite a bit). Upping 40% chances to hit to 55% chances to hit decreases the number of rounds by a minimum of over 25%, typically more. That changes a long drag out 20 round high level encounter to 15 rounds or fewer and decreases grind.
The only downside of the Expertise fix is that it's a "must take" feat, but many DMs houserule it in.