Narita Express, then regular JR line – how should I go about buying tickets? (Group travel)

Hello everyone,

I’ve used search and haven’t had much luck for my question, so I hope it’s not doubled and that the flair is correct.

I’m chaperoning a group of 15 minors on a trip to Japan. I’ve been many times before, but managed to avoid Tokyo city and the Narita Express before, so I’m a bit insecure regarding how to go about buying tickets.

We have time constraints and luggage, so the N’EX is our only viable mode of transport to get into Tokyo even though I’d prefer to just use regular JR. Then we have to change to a regular JR line to get to our destination. Starting time in Narita must be around noon/1pm (weekday).

The minors will receive Welcome Suicas. I have to buy my own paper tickets to present for reimbursement.

I am fluent in Japanese, but it’s my first time being responsible for people other than myself/minors AND my first time in Tokyo in general.

Should I:

(1) buy N’EX tickets + seat reservation online beforehand (in three/four steps seeing as I can only buy 6 tickets at the same time) and worry about JR regular line when I’m in Tokyo and

(1a) only buy the tokkyûken (super special N’EX fare) for the minors and combine with their suica while ordering paper tickets for myself

or

(1b) buy both tokkyûken AND standard fare paper tickets for all of use?

OR:

(2) go to the midori no madoguchi at Narita the day of and go “I have this group of minors, we need to go to \[end station\] at \[time\], we need to sit somewhat together on the N’EX, please work your magic”? (=> probably paper tickets for the whole thing for all of us)

My worry with my favourite (2) is that the N’EX won’t have 16 reserved seats close to each other if I buy the tickets just hours before we need to get on the train.

The JR Pass is not on the table.

Thank you SO much for any help you may be able to provide!