Dragonfruit is pretty. I'd happily grow the cactus for the fruit - did you know it flowers under the moon and if not pollinated, dies and produces no fruit? The sun is too harsh for the delicate flower, but gives the fruit its vivid coloring.
Sadly, dragonfruit isn't much of anything once you get under the skin. It's mild, and timid, and no amount of coaxing will embolden it. It's easily overwhelmed by other fruit flavors, but florals tend to complement it - rose, violet, lavender. But not too much, because even these delicate florals can dominate the mild, mild dragonfruit.
It's pretty, though. The pulp is a milky white with soft black seeds, very Goth looking. It's a good fruit for a zombie - all looks and not much else.
You really want dragonfruit to be spectacular, to wow your tastebuds as much as it does your eyebuds.
But it doesn't. it's not even all that nutritionally good, just - blah.
But rambutan - rambutan are pretty and bees love rambutan, and the fruit is sweet and mildly acidic, like grapes. It makes for a delicious jelly and a fine pie or fruit for a bread where one would use fresh grapes.