Hoov I'm an AAB guy and my Gold Strike experience was exactly as yours. I bought it thinking it was going to be the grail of all games and found myself "disenchanted" as you say. The game could drag on and started to feel monotonous. I'd start to zone out and lose interest. A couple times I actually shut it off. It was always fun for a game but not one that made me yearn to press start again and again. I have to think El Dorado in this case would be about perfect.
With that said a lot of AAB games are great fun. Getting to that next ball can be more exciting than popping a replay in the right game. It's like having an exciting game go into overtime. As shapshifter said though, the thresholds have to be right. No one respects a game that gives it away too easily. They have to feel earned. I have replay games and I still enjoy the thrill of beating the game and hearing that knocker. That's the goal and it feels great. With a good AAB machine you may get that thrill multiple times in one game. Your progress is saved and with each pop and the excitement builds. You may have a personal goal (high score or roll the machine) and each earned AAB gets you that much closer.
Alex