I am now reading the 4th book of the series, Charlie Bone and the Castle of Mirrors
. Next, it'll be Charlie Bone and the Hidden King
, then the first book of the Pendragon
books, The Merchant of Death
If you want an easy but in someway possibly challenging, but not challenging enough to confuse you or even come close to confusing you, but not too easy that your bored, and mysterious and adventurous, as well as a very well-written fantasy, including more than one point of view, I suggest reading the Pendragon
series. The first three have 300-something pages (with the second having near 400 and the first somewhat close but not as close), the 4th-6/7th have 400 + (I'm not really sure about the seventh, it may have more than 500, and the 8th having 569 pages. The ninth I believe will have 600+.