I don't think the economic model for worlds of fun has, or will ever, rely on appealing to a KC tourist draw. mainly because no such thing really exists. maybe you get some extra tourism 8 weeks a year during the (mostly wintery) football season, but KC is just not a magnet. worlds of fun's primary audience is entrenched KCers who still feel fondly about the park and will gladly visit once or twice a year, especially when they have young families. so it may be disappointing to thoosies, but the park's trajectory of opening a new mid-size coaster every ten years or so is honestly pretty good comparatively. and I think the mattel park is extremely far away from a reality at the moment, so I doubt that concerns them too greatly.
i would actually be interested in the numbers but i find it hard to believe that a large proportion of WoF attendance, or KC tourism in general, is pulling from the nebraska/OK/Iowa basin that doesn't have their own (major) parks.
for what its worth, I thought timberwolf actually ran pretty well when i was there last year. bit shaky and too much sideways jostling on old track, but I had fun. some new lighter trains would probably do a world of good