The appropriate rail pass for our trip

Hi everyone!

My friends and I are going to Japan next March 2019. So far this is our draft itinerary:

Saturday - Osaka (We arrive 11:40am at Kansai International Airport - Terminal 1)
Sunday - Tokyo (1 day trip only)
Monday - Universal Studios Japan
Tuesday - Kyoto
Wednesday - Nara/Kobe
Thursday - No plans yet
Friday - Morning (no plans yet)
-Afternoon (flight home)

Since we will be visiting Tokyo, can you please help suggest the right rail pass for our trip, that would cover both the Kansai area and our visit to Tokyo?

So far, just to share my initial thoughts, I am thinking that on Saturday night we get the last train from Osaka to Tokyo, so that we will save time instead of travelling to Tokyo in the morning (6am/7am) of Sunday. Is this a good plan? In line with this, do you guys know what time is the last train from Osaka to Tokyo?

Any suggestions or help from you guys will be much appreciated. If you have any revisions with our itinerary, they are welcome as well. :)

There is no overnight train that you can take to get from Osaka to Tokyo, if that is what you mean by "last train." You could consider overnight bus (if your body is OK with it and if your main aim is to save money). Otherwise, you might just want to take the first Shinkansen train in the morning.

When you say "rail pass," if you mean a nationwide Japan Rail Pass, if you get the 7-day Japan Rail Pass and use it for the Kansai - Osaka, Osaka - Tokyo, Tokyo - Osaka, then it will pay off (or comes out almost even). Since you can use it for shorter distances like between Osaka, Kyoto, Kobe, Nara, etc. it would pay off.

But if you use an overnight bus between Osaka and Tokyo, it will NOT pay off. JR Pass is good for long-distance (between cities like TOkyo and Osaka/Kyoto or Hiroshima) travel on JR Shinkansen.

Going all the way to Tokyo for say 6 maybe 8 hours and losing 6 hours in travel time seems silly.

I would use that day and all other free days to vist Kyoto.

Since you have two days with no plans, why not move things around and spend three days in Tokyo?

Generally speaking you'd probably just barely break even with a 7-day JR pass, and it's generally more convenient and flexible to just buy individual tickets with cash. With cash, you can take faster shinkansen trains, and you can take alternate railway companies (not just JR) when you travel around Kansai.