Japan in Dec/Jan

Hi, I will be travelling with a group of 10 people, and below is my itinerary. Would you recommend I take the JR pass (does it cover all travel) or should I book separate tickets. Thanks!

Dec 24- Dec 28- Tokyo
Dec 28- Fukuoka (Flight)
Dec 29- Day Trip Beppu (Shinkansen)
Dec 30- Day Trip Nagasaki (Shinkansen)
Dec 31- Fukuoka
Jan 1- Osaka (Shinkansen)
Jan 2- Day Trip Hiroshima (Shinkansen)
Jan 3- Osaka
Jan 4- Kawaguchiko (Shinkansen- Via Tokyo- Otsuki)
Jan 5- Tokyo (Train/Bus from Kawaguchiko to Tokyo)

Looking for advice, thanks in advance for any inputs! I was thinking of taking the 7 day pass, activating it on Dec 29, and it should cover us till Jan 4.