Well, since you are asking suggestion i guess you would want to avoid it but... this is what i have done: pruned. Hard. The sooner you do it the sooner the plant will recover from that.
I mean, once you get a nice structure you can go forth with tip pruning but till you don't have that, tip pruning doesn't help.
As you may know i have just a plant in the ground and the others in pots. So far i noticed that plants in pot are less vigorous of the one in the ground; with the plant in the ground i can see that, over the time, some buds develop in gaps in the canopy and fill them, while it doesn't apply to the plants in pots, wich tends to grow only close to terminal bud. So the best idea, to me, is to prune hard, eliminate the canopy, and redo completly the structure.
I have done that about a month ago to a kensington pride mango and i'm pretty happy with the results. If i can, i'll try to post a a picture of it later