The combat problems start with unlimited Long Resting.
They failed at introducing any kind of resource management into the game which skews the D&D classes that have been designed around a limited Long Rest.
It really sucks when you finally reach 11th level as a Wizard, only to find out that Chain Lightning doesn't kill minion level enemiea because their HP has been pumped to 50-60 and above. It feels weak. Martials are still fine because doing 60+ damage per turn and killing an enemy feels powerful.
