We have done two 6 week stays at WDW. They were amazing trips. We come all the way from Australia and visit every 2 years. Due to the cost of flights, it works out much better financially to take longer trips.
In 2013, we spent just 6 weeks at WDW. We arrived at WDW, stayed for 6 days, left to do a 4 day cruise on the Disney Dream and then came back for 5 weeks. We did the Halloween parties, the Christmas parties, the Wild Africa Trek. We slept in most days, hit the parks late and stayed until close (there was a few 3am MK closes) We took things as it came, if we wanted to stay around the resort we did, if we wanted to head into the park we did. It was a wonderful way to just relax.
In 2015, we had a 6 week trip. We stayed at AKL for a week, left to do a 7 day cruise on the Disney Dream (back to back 3 day and a 4 day) and then back to WDW for 4 weeks. We toured exactly as we did in 2013. We slept in, we closed down the parks. One day due to the park being rained out we were literally the last people in the park. We rode the Mine Train 10 times back to back. We had no idea there was no one left in the parks until a few CMs along Main Street told us the park was literally being kept open for us. Security was waiting for us to close the gates. Apparently we had been the only people in the Kingdom for the past 50 minutes. We felt bad keeping everyone (the park hadn't passed the official close time, the rain had just been that bad and it was almost midnight) but it was also amazing to realise we were the only ones in MK.
Anyway, long trips are truly amazing. No pressure to "have to do something today", our maximum wait time is 20 minutes, if we feel like leaving the parks we do.