I have to agree with the people that say it's easier than some of the past games. Maybe first time you are going through or don't know much or anything about Pokemon is when it's a bit difficult but still gives you enough help.
Also level grinding is not that neccesary since they give you the Lucky Egg like mid-term into the main story, i think. And if you use the Pokemon that were almost given to you before each gym, you can beat the Elite Four with little to no problem. Sandile's last evo gets rid of the Shauntal member and Catherine which you get before the 4th gym, Galvantula can take out almost every Pokemon from Grimsley except maybe Pawniard but if you got a Fighting early in the game it should also be a piece of cake. And for Marshall you could use a Swoobat, which also helps with Burgh and you get it early.
The most difficult part for me was the Ghetsis fight, damn Hydreigon killing everything from my team
and the post-game was also a bit difficult.