I've futzed around with using other fruits before. The problem with using whole fruit is the pulp - it makes a drink thicker and the pulp can separate if it sits for a while.
I haven't done the blended thing before, but if you're going to use fruit, make sure the fruit is super ripe and flavorful because the lime (or other citrus) tends to dominate other flavors, if you really want a fruit margarita. I did watermelon (it was okay; not a strong watermelon flavor), strawberry (it was stronger flavored than the watermelon). But, personally, I ended up much preferring a traditional style (citrus) margarita.
I would also consider separately pureeing the fruit, then putting it through a medium mesh (to limit the pulp but not eliminate the pulp) or a fine mesh strainer (to nearly eliminate any pulp) to get some pulp out since you're thinking of blending it with ice. The pulp will thicken the drink, but since you're blending it with ice, which will thicken the drink anyways, you may end up with a really dense drink.