An elimination of an Express Pass would certainly dampen my excitement for HHN. As a traveler who would only get to be there for one or two nights, maximum, the possibility that it might turn into a churning slog of waiting in line for a solid hour or two multiple times and only getting to go through 3-4 houses per night would be a pretty big turn off. I'd really need to see how the event appears to be going down every night. If attendance is capped small enough and the system works itself out well enough that all the houses are doable in one full or two partial (thinking like four-five hours per) nights if you're smart about it I'll still be fine making the trip with those circumstances in mind.
If it swings the other way and just turns into too much of a chore in between houses, I'd likely lean towards skipping. Seems like it'd be much more worthwhile for locals, even if it means they need to go three-four-five nights to experience everything. Which, honestly, wouldn't be a bad gameplan if long distance travelers will all but evaporate for this year's event; might as well make it an as-many-nights-as-necessary event for locals, one way or another.