Every time I see threads like this it blows my mind at how there is still such a widespread misconception of Epcot

.. Epcot is my favorite WDW park and IMHO is one of the most underrated parks, there is just so much to see and do at Epcot, I have visited this park hundreds of times and I still get just as excited as day one every time I have a chance to visit..
With that said, to answer the OP's question:
First and foremost a visit to Epcot is not complete without going on SE, this is a legendary staple attraction for Epcot, so that's another attraction you can add to your plan and it's family friendly so everyone in your party can ride it together.. The SE post-show area is also neat and has a few things there to keep the kids entertained for a bit before going outside again..
I also see that you entirely omitted the WC side of the park (outside of Akershus/FEA)

.. Each WC country has lots to offer and enough to keep you entertained for hours, there are several rides/attractions/shows (GFT, AA, films at China/France/Canada, street performers, etc.), lots of unique shops and kiosks, beautiful scenery/areas for family picture ops, and there is also lots to see and do for the kids, as stated by pp, each country has a "Kidcot Fun Stop" area with kid-friendly activities (arts/crafts/stories/etc.) and unique CM interaction opportunities with CMs that are actually native to the countries they are representing which can be both fun and educational.. Not to mention, a visit to WDW is not complete without seeing Illuminations
Hope this helps!