And about Osaka
As Homerduff wrote above, it's quite different from Kyoto.
Both of them are busy cities today, yet the traits are different.
Kyoto is a city of sightseeing and academic/business, etc.
It has a rectangular street system, like a chess board.
Because the Emperor had lived there,
it was the capital of Japan till the end of
Edo era.
So there are many historical/cultural sites.
Osaka is a city of business and academic/sightseeing, etc.
You can enjoy the chaotic mood of a big, bustling city there.
Besides, the people of Osaka are not so shy as average Japanese,
and friendly, I think.
If possible, it would be interesting for you to see
two different faces of Japan in one trip!
There is an old saying in Japanese:
"Kyo(u) no kidaore, Osaka no kuidaore."
This means:
Kyoto is the city where people spend much money on their clothes
untill they go bankrupt.
Osaka is the city where people spend much money on their meals
untill they go bankrupt.
Anyway,
don't miss sakura!
There are so many cherry trees all over Japan, though.
Both in Kyoto and in Osaka, you can enjoy them.