worth buying JR pass ?

Hi
I leave Canada on 16nov. ....my itinerary on train would be
1) Tokyo- Ito direct with LTD EXP Odoriko or, via Atami with Shink. Kodama & JR Ito Line Hyperdia quotes 2310Yen no seat reservation
2) Ito-Kyoto via Atami witd LTD EXP. Odoriko & Shink. Kodama or via Atami & Mishima with JR Ito LIne plus the 2 already mentionned.......quoted 7180 Yen ,no seat reserved
3)Kyoto- Narita airport...with Shink. Nozom (not JR pass) or Shink. Hikari via Tokyo. both are quite similar price +- 10,000Y no seat reserved
Am I right thinking that if I don't reserve a seat(any obligation ? ) the JR pass at 29,100Yen is not a deal or should I not take the risk of being left on the pier ??
Is it too late to buy the pass as I leave in 16 days and live in Canada ?
I will be waiting for your advice
Andree