Seoul or Tokyo or Singapore for Short Vacation?

Just wondering which one of these there would you recommend for a short (3-7 days) vacation/trip in August? Not looking for shopping or adult recreational activities. Look mainly for place with good food, sightseeing (cultural/outdoor) type trip.

Those three places were selected since they were stopover locations from where I will be traveling from in China to my home in USA so just looking to take a trip since it would not cost me much more airfare wise.

thanks,

John

wow--I wouldn't chose any of them! My preference would be Bangkok or Hong Kong.
I've not been to Singapore but my family just returned. Very modern city, but great food. Expensive hotels--they used Starwood points and cash to get a reasonable price. Much more $ than Thailand.
I only spent time in ICN and NRT and their airport towns. I do know trains take almost 2 hrs to get into Tokyo and Seoul proper.
I have read about some homestays in South Korea, but not very familiar. Tokyo hotels are $$$ but the LL deals are pretty decent. One thing that might be of interest is the DMZ tour (you can arrange through your service branch if you've been in the military ) or take a regular tour.
We're going to Bali via BKK (or maybe SIN if flights look poor--we travel standby) next month.
Do you have any other options for stopovers?

I will be leaving from Wuhan, China. Not interested in any china locations and have already been to Taipei & Hong Kong before. Have been to Bangkok before and will probably choose it for return trip stopover.

Wuhan Tianhe International Airport - Wikipedia, the free encyclopedia

If you lean at all toward one stop in Bangkok--have you been to Hua Hin? It's just a few hours southwest of BKK and fun place to chill out at the beach. LL has lots of great places there--good for 4-5 days.
I can't tell you enough about Singapore but I may be stopping there for a day or two. Seoul could be interesting, but I'm not too big on most of their cuisine.
I wonder if you can find any special events happening in August to steer you in the right direction.