As an example, it took Dabo, another first time head coach (who inherited a better roster in a weaker conference), about 4 years to get them really going good (10 win seasons, conference title appearances, big time bowls) and then they stalled at that level for a few seasons, and then by year 7 they were really elite (perennial national title contender).
I think it's reasonable to expect Coach Pruitt to have us very good by year 4-5 (10+ win seasons, division titles, big time bowls), and if he's truly a special/elite coach like we hope, then by year 7-8 we could be where Clemson is now (perennial national title contender).