Originally Posted by
mingw
unfortunately I didn't think of the overnight bus choice before. otherwise it sounds a great choice. I already booked hotels and both are non-refundable
although I don't agree shin-osaka is at city center

my hotel is sheraton at uehommachi station, and it would take about half hour with at least one transfer to get to shin-osaka. I'm not sure whether I can get the ticket at uehommachi station? it's not JR line if I'm not mistaken.
JR stations are not the only place you can purchase JR ticket!
At Kintetsu Uehonmachi station, lower basement level of the station where tickets machines for Kintetsu line are located, there is Kinki Nippon Tourist travel agency. You can buy JR ticket there. This location is open Mo – Fr 10:30 a.m. to 7:30 p.m. and Sa, Su, holidays 10:30 a.m. to 6:30 p.m.
Travel agency offices around town are still common in Japan and you can purchase JR tickets at any major travel agency in Japan.
Yes, you can activate JR Passes only at specific JR stations. But as far as purchasing JR tickets for Shinkansen, Express trains, etc. you do not have to go to JR stations! Whatever reasons, making use out of travel agencies in Japan is never talked about here at FT.