Do you have a wealth score in mind to be able to do the Build a Great Hall activity? My gut tells me you would need to be 4+ to afford it. That said, you could probably still host a feast in a rented hall for less. As a director, I would want guests to be able to benefit in some way from the extra recoveries. If my players held a feast, the BBEG or the devil that consistently offers them bad bargains would be sure to attend.