First and foremost, if you like driving and have the time, while your wife and daughter don't, then the plan for you to drive the family car (I presume) to New England and get a little 'guy stuff' in along the way is an excellent use of resources. A few things that occurred to me immediately on reading your post were these:
1) You should really try to be in New England on the 4th of July if you can possibly do so. A small town parade, or fireman's breakfast, or historical pageant would be great. Not spectacular by any means, but a real piece of Americana. Also, just hanging out in a small town means that you can miss some of the holiday traffic.
2) Portland may not be the best bet for your wife and daughter to fly into. There are no direct routes from Lambert to anywhere I would suggest, but besides the airports that you and glc mentioned you should look at Syracuse NY as well. It is both typically cheaper than Portland and gives your wife and daughter the chance to see more of New England. The cost of flights to Portland start to rise steeply around the 4th of July. Flights to Syracuse don't. Exact costs will depend largely on the time of day of the flights. Two other possibilities worth checking out are Albany NY and Burlington VT. Just make sure that you leave plenty of time for them to make whatever connection they need to. Airline schedules are still not back to 'normal'.
3) As a former New Englander (NH and ME) I would strongly recommend staying in northern New England (ME, NH and VT) if you really want the Yankee vibe. Capes Cod and Ann are nice (and crowded), but the many capes or headlands between Brunswick and Waldoboro ME are just as scenic with far less traffic.
So those are my main general recommendations. Once you have a working outline of a plan, I can certainly be much more specific about places I would try to hit. BTW, many of those suggestions would depend on how old your daughter is, so please let us know.
AZBuck