I love my Strawberry Kiwi Apple cider... not sure about adding mango and pineapple. Pineapple would boost the acidity level a lot it seems like... Do it and let us know how it goes!
I've never used pectic enzyme. Usually I just add gelatin to fine it at the end. I figure I eat enough pectin in my daily fruit not to worry about it. Anyone who tells me my cider is hazy gets cut-off. And gelatin does a pretty good job of removing haze.
As far as a recipe I'd probably do:
4 parts Apple Juice
1 can Strawberry Kiwi concentrate
1 can Mango / Pineapple concentrate (Tropical Flavor?)
And top off with water / AJ depending on OG.