I would only suggest this to someone who has already spent a good amount of time in Tokyo, or for whatever reason, does not have time to leave the general Kansai area, or wants to stay in a single specific hotel and hit Kyoto, Nara, Kobe and Osaka. Osaka has its charms, to be sure, but it is not different enough from Tokyo to warrant much time for the first-time visitor. If the castle was decent, that might change the equation, but to me the Kansai cultural differences and food culture are not enough of a reason to spend limited time there. Kyoto has lots of pros and cons, but it is diametrically opposed to Tokyo in so many ways that it is the perfect counterpoint in a short itinerary. In fact, I'd probably suggest Nara and Kobe before Osaka.

I'm not disputing your personal reasons for favoring Osaka. However, for most tourists, would you really steer them away from some of the most stunning temples and shrines in the world to go to Osaka?