It depends on your pace, what type of food you can live on, mail drops, and how much food weight you are willing to carry out of town. You can look at the mileage between towns on the trail and grocery stores just off the trail to estimate how many days between stops to maximize time on trail while adjusting for a slower pace starting out and a faster one once you get to Damascus. It is all good practice and learning the order of towns and how far left or right is very helpful. Don't focus too much on the details. After a month or so the trail becomes life and you will find you are still the same person inside. Unless you are really disciplined and motivated in the real world, well laid plans aren't going to work on the trail. Are you looking for memories or change? The best memories cannot be planned. The change you get is a much better understanding of your physical and mental strengths and limitations and the cost is a lifetime of subtle loneliness and a once yearly longing to return to the woods.
I did like most people do before I started. I got the books, maps and made plans of estimated dates for towns for mail drops and supplies with estimated mileage and dates. It was like dot to dot. From home plans were like, Tuesday August 7th should be a 28 mile day between these two shelters because the profile maps shows little elevation change and my pack weight will be light as I will be 2 days from a mail drop. My notes should have been burned after the first day's failure, but I kept them as a reminder of my arrogance. I didn't plan on using hostels,hotels, and was going to avoid most of the off trail hiker towns. I couldn't afford to go all out. My last minute gear splurge ate up a month of estimated hiking cost. I ended up spending about $2800 for six months and six days. Most of it was food. Four hotel nights. I bought some fast food and buffet meals and a couple $40 restaurant meals. I was so cheap I stayed at Shaw's and didn't buy the breakfast.
I was able to avoid many of the hiker towns that are a few miles off trail by carrying up to two weeks worth of groceries out of town and loading up on junk food and perishables at small town convenience stores. I did avoid most hostels, all the huts, and a lot of other interesting hiker stops. I was out of season so some hostels and trail magic regulars weren't around. Towns aren't as interesting and people aren't as friendly when you are a lone dirty hiker. Most of the Northbound hikers I met in town were very friendly and we traveled in small groups around town and had good times. Many would have made good hiking friends but our stories weren't the same. I can remember moments and places but not their faces or names.
My Southbound experience is going to be way different than your Northbound. I started May 15 and rarely saw the same person twice. There were 4 of us just out of the Wilderness in Monson over two days. At Gorham we were only two and we had good times touring the town, dining with attractive young ladies, and sharing stories of the past few weeks. I never saw him after that. It was Roan Mtn before another Southbound hiker finally caught me. Northbounders have the opposite problem. The first Northbound passed was in Hanover, from Manchester Center to Unionville I saw lots of them every day. The best memories you will have is of time spent in town with your hiking buddies.
When it is all over you will remember the sunrise from Grayson Highlands where the fog filled the valleys leaving only the tops of the mountains looking like islands in a cloud sea. The cold morning when you first succeeded at lighting your stove and boiling water using only one hand extended from the top of your sleeping bag.
The best stories come from adversity or strange pleasures. All your gear is soaked and you needed some sunny place like a parking lot to dry it and a wind gust blows your tent into traffic. You landed in a small town for a mail drop on Sunday afternoon and got the move on from a town cop caught you sleeping in an alley behind the Post Office. The feeling of putting your feet into warm soft socks straight from the dryer after a week of putting them on crunchy. All alone at dusk on a blue blaze to the shelter throwing rocks and doing bluff charges at a large black bear that wants a handout and is blocking the way.
On the trail you will hike alone while being a member of a loose band of other individuals. It is very easy to make friends as you all share a common goal, have similar stories, and know the same people. Spend time with these people and have fun. Most of them are on a budget too so prearranging a 4 way split on a hotel room saves everybody money. Towns and hostels hold people for a couple days so they are the best places to catch up with old friends and meet new people. Some of the best memories you will have on the trail is of the time you spend with these people in town.