In this game, I'd say that's just as it should be. In a group it gets ten times easier but as solo I think it's fairly balanced.
I think the beginner maps are great for learning your class as a new player. New players are flooded with info and have to learn all their skills and traits as well as everything that goes into the combat system like Utility, Conditions, Stunbreaks, CC.
For me, the core game is mostly a fun learning experience and from HoT onwards is where you put that learning to use on harder difficulty maps.