Perhaps the big flaw in your question (So what aspects from each era would you use to create the best product?) is that the best product is irrelevant today. Vince took wrestling and made it entertainment. Plain and simple. The whole reason TNA boomed was because it focused more on the actual wrestling, which caters to the likes of actual wrestling fans, but not to the mainstream or lay-fan. Most importantly, it doesn't cater to kids, who buy the toys and nag their parents to purchase anything related to their superstar of choice.
The 80s is when this whole thing began, and Hulk Hogan was the culprit. Similar to Kiss and rock n roll, the "music" didn't matter so much as the spectacle. Sure it was wrestling still, but that wasn't the point anymore. Bruno Sammartino is old school, but that wrestling is simply not fast enough or flashy enough to get the attention of the majority. The 80s were a time of transition, so as much as it seemed like the decades before, it was moving in a totally different pop culture direction.
All we can really ask for is that TNA blossoms into a legitimate threat, so that WWE is forced to focus on their product. It's no wonder that the best time in recent history was the Attitude Era, which was an evolution of maximizing profit AND product, and the reason that mattered was because WWF was competing with WCW. Once WWE has a monopoly (again), the product will shift down to PG rating (like it is) and the product becomes rubbish