They may not have enjoyed it as much as I did, but they were interested in doing further adventures using the One Ring, especially once the Moria expansion comes out.I don’t want to invalidate your experience, but are you sure your players enjoyed it as much as you did?
If you asked our DM about the introductory adventure, he would probably say it went well. He was enthusiastically pushing for the adventure (since he is a massive Free League fan and really enjoyed the One Ring) and the players all recognize that as DM he put more work into the adventure than we did.
At the end of the adventure we weren’t about to point out the adventure’s shortcomings as an adventure, particularly since we weren’t starting a One Ring campaign.
We didn’t point out the adamantine rails we were on the entire time, nor that it kind of sucks that the Keeper can just decide when an enemy hit 0 hp that the enemy can just escape, come back to life or be killed by the sun coming up. Or the unnecessary dice rolls. Or that the adventure felt thin on content.
Also regarding rails, as a group we tend to stick with published adventures these days as takes less time / stress for us, and recently completed Shadow of the Dark Queen, which I Felt more rail roaded than this outside of the Northern Wastes, and we all enjoyed that nonetheless and played it through to completion, and are working out which game rules / published adventure we will do next.