This is an excellent idea that really needs more traction. Even more so since there's been 2, soon to be 3, Ages released since this idea was put forth.
The players need something to help cut down on the times, not only to reach these ages, but to do so in a manner that keeps their abilities somewhat on par, not necessarily even, with those players that are putting in the money.
I could not have put it any better than {[Fresh]}Kratos, this is perfect match thematically with the war academy. Even just the Tactics and Generals tabs would be fine.
In addition to this, they could still have a tradeoff in times by extending the upgrade levels of the Academy into the current ages. It would still be a net gain for the players, but not as one-sided, while keeping another building relevant through the ages.
There would be some disgruntled higher aged players, because who wouldn't be unhappy at such a feature becoming available when they had to do it the hard way, but this would be mitigated by both their ability moving forward to utilize it, and the lower players making some headway towards having real involvement in Wars and whatnot.