Swindon's form under Holloway has been nothing less than outstanding, now hard to beat & you always seem to get a goal when you need it from what he's coached into & instructed the players. He's set a yardstick for the division so I hope Hughes is working along the same route with Carlisle.
Iirc IH as used the squad you already had which shows the effect a manager/hc can have with a slightly different approach & directing them to do things in games differently. I hope your "popular" owner sees it that way & backs him for next season so he can continue & improve what you have.
The ex MKD coaching staff are the kiss of death (e.g. MW) so expect the Gills to come onto it now, probably playing possession based football & being caught out in their own half.
Nobody's "too good for non league" and if that's what they believe it's where they end up. He's slipped down the football ranks for a reason - as they all do.