The Mortal Instruments series by Cassandra Clare is really good, it has several of the creatures you mentioned as well as something entirely its own.

If magical ninjas appeal to you at all, I'd recommend the Tales of the Otori series by Lian Hearn. The first book is titled Across the Nightingale Floor.

If you like mythology then I'd suggest the Everworld series by K.A. Applegate. The books are short but there's a lot of them and it has a very original concept that is rather well-executed for a young-adult series.

You found the perfect guy for you job...I've read maaaaaany books of fatasy and I stiil read...I recommend you to read:Percy Jackson and the Olympians series...you'll love them and maybe found them better than Harry Potter...Then u can read Septimus Heap or Charlie Bone.I also recomment A Series of Unfortunate Events which are great.I don't know if in your country has been published the Stravaganza series...but if the series exist add them on the list...

I'd definitely recommend Robert Jordan's Wheel of Time series. They are absolutely amazing books, loads of plot twists. There are thirteen of them at this stage (including a prequel) and they are all big books so there's loads to read. Plus there are still more to come.
They are fairly hardcore fantasy, think LOTR without all the singing elves.