I’m currently saving up my gold to unlock a new Solo Adventure since I’m not interested in purchasing the Festival Of Legends Mini-Set.
I dislike the one’s that require a pre-built deck like Knights Of The Frozen Throne and am looking for replayability, a lack of repetitiveness, and most importantly … FUN.
the only adventures that match your description (no deckbuilding) are…
kobold and catacombs (dungeon run) only has original 9 classes very replayable, and fun.
witchwood (monster hunt) only has 4 classes, some unique mechanics. has a final boss. it fun the 1st time. i don’t replay it much
boomsday project (puzzle lab) very fun the 1st time. after you solve the puzzles though, there is no reason to replay it.
rastakan’s rumble has 9 classes very easy and unfun
dalaran heist has 9 classes 5 chapters each with a unique twist. also can add a random anomaly to runs i have almost beat all chapters with all classes. probably my favorite, along with dungeon run.
saviors of uldum (tombs of terror) 4classes 4 chapters each chapter has a final boss with 300 life that can be killed in a single run, or over the course of multiple runs. can also add anomalies to these runs. i have %100 this one prob. my 3rd fave.
book of heroes tells the WOW lore of the original 9 characters. good story, but not very replayable
book of mercenaries same as above only it is about the mercs introduced in barrens.
hope this helps. good gaming to you.