I'll handwave the viability issue and just focus on interesting.Anybody on this list that looks interesting and viable?
Eusebio di Francesco - Has a high-intensity, exciting style featuring a possibly suicidal amount of pressing. Would establish football that's super fun to watch if we didn't get absolutely clowned by turnovers leading to counterattack goals.
Claude Puel - Pragmatic and has a track record of getting decent results out of middling talent. Drummed out of Southampton and Leicester by fans who thought he was too boring both personally and from a footballing perspective, but a better manager than it would seem after being sacked by two mid-table Prem sides.
Domenico Tedesco - Has a pretty "go for it" philosophy. Possibly one of the more exciting prospects on the list stylistically. Did very well with Schalke until the organization hit a wall and he was sacrificed (they sold Goretzka out from under him). Would be used to a higher level of talent than we have but not a *radically* higher level.
David Moyes - A super unsexy option but sexier than Big Sam. Pragmatic and would actually probably use our talent edge over most of the league well, but possibly conservative to the point of boredom.