I took my BFF for her first trip as an adult in 2015 (we were both 51 yrs young
) She could never understand why I enjoyed it so much and went so frequently, and only agreed to go after I said we would rent a car a go to Universal a couple days for the Harry Potter stuff. Stayed at three resorts - Jambo House for first night, then OKW for 4 and Poly for 4. First off, she was really impressed with being able to check the luggage at the airport and then just boarding DME at MCO and not worrying about the bags. Huge convenience for solo female travelers our age! Also, never underestimate the power of a savanna view room! She was up at 7 AM that first morning FaceTiming her sister to show her all the animals. That was Saturday morning... We had flown down early afternoon on Black Friday, and I added one day DlxDP. We did the Fantasmic package at Hollywood and Vine that night, and then used the other 2 credits to do a Candlelight Processional package Saturday for an early dinner.
After moving to OKW on Saturday she was already impressed (because they were taking care of transferring the luggage!) and mentioning how cool it was to experience different styles of resorts. And she was like "maybe I need to speak to someone about DVC...". By Sunday she had scheduled an appointment and on Monday she bought Poly points!!!
When planning the whole trip, I asked her a few questions, mostly about places to eat, but otherwise she was happy to have me make all the decisions. I had her look over park maps so she would at least have an idea of the layout, and we talked about a few of the rides. I tried to not make too many specific plans, and made sure to highlight some of the unique things - like Jambo house, and the seasonal offerings at the parks. I made our first meal a character meal so I could gauge her willingness to interact with them, so I would know whether or not to fit in any character meet and greets. One of the few things I booked to help her really get a feel for the Disney vibe was the Osborne Lights dessert party. Maybe you can find one special thing you would both enjoy and book that. Magic Kingdom was actually the last park we went to, just because of the way some of our special events were scheduled. After your first visit to each park, see if there is something she enjoyed and wants to do again.
The funny thing about the whole experience is that she turned her ticket into an annual pass and went back 2 weeks later with her sister! She now visits as often as I do (if not more!) and still regrets she refused to give Disney a try for so many years.
Whatever you do, it will be fun and magical because you are spending quality time with a great friend. I see your dates put you there right towards the end of Illuminations, so I would probably try to see that one of your first nights, unless it is a weekend night. I already don't like how boozy the crowds get at Epcot during F&W weekends, but it will be even worse with everyone trying to go see that one last time.
Have a great time!