Hmmm, I don't know about that. Using that logic, the Horizon League and the WCC would get multiple bids every year, and that doesn't always happen unless someone other than Butler (last year) and Gonzaga (this year) win their respective conference tournaments.
I think the Valley will get multiple bids next year because we have several veteran teams coming back. But that will have less to do with a Sweet Sixteen or even Final Four run by UNI than by teams who earn their way in like the MWC and A-10 had this year.
Besides, Memphis's multi-year run of Sweet Sixteens and Final Fours did nothing to garner multiple bids by CUSA until ironically this year when Memphis fell to NIT status! More a little luck for CUSA this year than anything else.