I hate, hate, hated running Dragon Heist and severely cut it short. Icewind Dale has some major problems, but for the most party they're easily fixable ones. Change a couple of story elements, ignore the quests you have the most issues with, and use the quests/encounters you like pretty much as is, add some foreshadowing and some rumors/leads to other plots, you're good. In general, coming up with some extra information/lore/rumors/etc. for the PCs will make the adventure shine a lot better.I agree. Some people, with a huge amount of work, apparently made it work for them, but for us it was really a horrible adventure, total railroading and not interesting at all, a large part wasted by "replayability" (stupid concept honestly).
Dragon Heist, on the other hand, absolutely will not work with giving the PCs additional information because the way it is written it spoon feeds the barest minimum of information to the PCs to get from Encounter 1 to Encounter 2 to 3,etc. (in a straight line) with usually only one given way to progress, and actively considers it to be "cheating" if the PCs try to think intelligently and actually get to their end goal any quicker. To fix the issues, I would basically have to rewrite a lot of the encounters entirely.
Ironically enough, even though it doesn't make any claim to replayability, I think IWD has a lot more potential for replayability for the same group of PCs than Dragon Heist. You'd probably have to tweak the second half of the adventure to mix things up, but PCs could do completely different quests from levels 1 to 6 or so.