Osaka-Kyoto-Tokyo

Hi,

I'm travelling to Osaka-Kyoto-Tokyo with the following itinerary.

Arriving in Kansai Airport at night
2 days in Osaka
3 days in Kyoto
6 days in Tokyo
Leaving Tokyo via Narita Airport

I'm thinking of getting a 7 day JR pass for use from the 3rd day in Kyoto and then to travel to Tokyo. It is worthwhile using the JR pass? Or should I just use single trip tickets?

I noticed that for return tickets, it makes sense as the to and fro trips already makes the JR pass worthwhile. But since I'm going one-way, does it still make sense?

Thanks