Making Birthday Plans

We have hit a bit of a conundrum when it comes to planning a birthday trip for my wife and I. We are looking to travel in March and are torn between splitting our time in Seoul, South Korea and Osaka and Kyoto, Japan, spending the entire time in Korea, spending the entire time in Japan, or going somewhere completely different. We both like the idea of a beach but know that we would both go stir crazy after about three days. Now, if there’s a beach destination that also has some city exploration close by (within a 2-3 hour flight) then we may just be sold on that.

I have gone back and forth on the different options and just need to make a decision. Any ideas or suggestions? I am open to ideas and would love to know how other folks have explored Asia. If you are asking “why Osaka?”, after a bit of reading, it is definitely a food city and I love the possibility of exploring a town by simply eating my way through it.