I haven't tried WL yet...next trip! We did stay at AKL last month with our kiddos, 10, 9, and 16 months and we all absolutely loved it. The atmosphere is very relaxing and we did not find it too dark at all. It isn't glaringly bright, but if it were it would detract from the theming, so I'm glad it isn't. It seemed that the moment we stepped into the lobby at the end of the day we were instantly relaxed, you really do forget you're in a theme park resort. The kids loved the pool, it's huge. They also played on the playground, got into the hot tubs, and liked viewing the animals. Seeing the giraffes outside our balcony every morning was such a wonderful experience! Even the baby would run out there every morning to watch them have their breakfast. We all enjoyed the gift shop, there are some really unique things there. The bus service was excellent, we never waited more than ten minutes and the buses don't stop at any other resorts. There are also lots of activities but we didn't do any of them.
However, DD and I are going it alone next trip. She will only be three so I've decided to try WL for the convenience of the boat to MK.
With the ages of your children, though, you will probably not be spending all of your time at MK, so AKL should be great for you. MK was the farthest away, with probably about a 20 minute bus ride. AK and MGM were quite close, maybe 5-10 minutes, and Epcot was maybe 15 minutes away.