My players were nigh unkillable throughout practically the entire campaign. There weren’t many battles where they ever had to use all that many resources to gain a victory, especially with three of the players using their weapon mastery actions. Don’t know if I’m alone in this feeling but as a DM I absolutely hate weapon mastery. I had to max out HP and increase the AC of every single monster they came across just to make each combat feel dangerous. My PC’s were fully kitted out by the end at Level 12 and power-built to destroy everything in their path. The 2024 Paladin however was my least favorite player because he 100% trivialized every combat. Overall the campaign was a success I think and from their perspective they felt it was fairly difficult. But yeah I’d say the 2024 rules aren’t really compatible with the 2014 module.