I think that most people on this board tend to overrate Kyoto and knock Osaka too much. If you are going to stay for only a short while and plan to spend most of that time exploring sites in the immediate vicinity of Kyoto, then staying in Kyoto makes sense. However, if you are going to explore the entire Kansai area, Osaka is more central in location, has better rail connections, and tends to be cheaper than Kyoto.

As you are going to only spend 4 or 5 days in the Kansai area, I would recommend staying in Kyoto and spending 3 or 4 days in Kyoto proper/Uji/Kurama and maybe 1 or 2 days on day trips to Nara and Mount Hiei. Trying to pack in Osaka, Kobe, or any other places would be stretching yourself too thin.