Purely anecdotal:
Petrie Dish - Bret Boone - before juice testing vs. after.
Many of your points, however, are completely valid, particularly expansion, the subsequent dilution of the pitching pool, and new bandbox ballparks.
And, no, Rose doesn't belong in Cooperstown.
The incredibly shrinking strike zone, shorter walls, shorter distances down the line and power alleys, Mile High thin air, about 700 theories on a "juiced" ball....the list goes on and on.