Best ticket purchase?

Tentative plan is to pre-purchase a JR rail pass before departure, then purchase suica card and portable wifi upon arrival at the airport while picking up the JR pass. Is it possible to use kuroneko service here so I will not have to carry Omiyage? I will be traveling with just a small photography backpack and an airline hand carry rolling suitcase. From Haneda I will go to Mishima Shizuoka ( suica card?)and be on my own for 4 nights and doing day trips for sightseeing and photography . I may do a day trip back to Tokyo on the last day(suica card?) before I move on to Kakegawa City Shizuoka (suica card)where I will spend time with a friend until Golden Week is over. While I am with this friend we will travel by automobile. Is is possible to activate the JR pass in Kakegawa City? Then traveling on to Miyazu-shi Kyoto,for 3 nights, on to Gifu, 2 nights,on to Karuizawa, 2 nights, final long distance leg to Akihabara 3 nights. Wth the JR pass. Should I purchase a 7 day JR pass? It seems I will be short one day. Will a 14 day pass be wasted, or will the leg from Karuizawa to Tokyo justify the expense? Should I buy the green car for a guaranteed seat?

Thank you very much for your help!

Use Hyperdia for routes and fares.

Is it possible to use kuroneko service here so I will not have to carry Omiyage?

Yes, many souvenir shops offer the service. The post service is also available, post offices also sell boxes and other packing materials.

From Haneda I will go to Mishima Shizuoka ( suica card?)

No, Mishima station is outside the Suica area, and in any case, you cannot normally use a Suica on Shinkansens. Use your JR Pass if you buy one, or buy tickets. Likewise for trips from Mishima.

Is is possible to activate the JR pass in Kakegawa City?

This type of question is exactly why I reject the term "activate" for rail passes. You can choose the first day of the validity period of your pass at the time you exchange if. After that, you have nothing to do, the pass will be valid from the day you have chosen.

Thank you for responding to my inquiries. My trip has been planned spur of the moment, in addition to trying this for the first time. Thanks for your help!