I can see an in-park preview center boosting sales. Back in 1992, when Mom and I purchased, there was less sense of "time is so precious in the parks" by potential buyers. We stopped at the EPCOT DVC info desk, which was located in the exit area for Spaceship Earth at the time. They really wanted to drive us over to OKW right then, but instead we had them pick us up at the Contemporary where we were staying, first thing the next morning. Bear in mind that we were staying 2 full weeks that trip, AND had plenty of time to see things besides the parks. Back then, a full week trip was pretty normal.
Travelers today may stay 4 to 5 nights at most, especially to cut costs, so park time is far more important to them. They'll be far more likely to do walk-thru type thing in the park than to have to be transported, do the tour, be transported back, and re-enter the park. And since it was a large unused spot, they put it to use. Another space large enough would be to reuse the Millennium Village building, but they do still use that for convention groups and special events. Or the Wonders of Life building, but I think they'll want to use that for an attraction of some kind eventually. I hope they can come up with a better use than a PLAY pavilion, though. They could us another omni-mover based ride, but they'd like need to expand that building a little bit. The omni-movers seem a bit more reliable than the current generation of trackless ride systems. Since there is no actual "sensory lab" in the imagination ride, maybe they could do something based on that.