Osaka is ok, but if you plan things right I think you can go for a 1/1.5 trip to Himeji and Hiroshima on the Shinkansen with a stop in Kobe (maybe over night if you want). Shinkansen is very comfortable. And, if you have a bit of courage and avoid eating out of the guidebooks pushing folks like Ramsay (and who knows who else ..... maybe even Rachel Ray's ideas) you can eat terrifically for reasonable price (as listed above, Y700-1200 for ramen & udon; Y1000 for good okonomiyaki, etc, etc.). Of course you can go up from there, but you don't need to.