That's a wonderful and charming neighborhood--close to town, train and the park. As you may already know, Northbrook is a bit different than most of the other North Shore villages in that it has several different K-8 school districts--most of which feed into Glenbrook North High School. Are you targeting district 28, and if so, are you specifically interested in Meadowbrook Elementary School? If you are open to considering some of the other schools and districts within Northbrook, you would have more choices.
In terms of the construction projects you described, I think that the time, money and effort that you would sink into that extensive structural renovation would not pay off down the road. Adding a basement is difficult--and depending on the water table level there, it might require even more engineering "tweaks." It's also important to make sure that any renovations you make to a home are in sync with the immediate neighborhood in order to retain the property's value over time.
Let me know if you'd like to explore some other options that would fit your criteria.