Eragon was bad. Just bad. Imagine a fanic Marty Stu
, then add massive amounts of unexplained Black And White Morality
that we need to take for granted - rather than shown, because failing the old rule "Show don't tell" is so "kool" -, plus uninventive and ridiculous worldbuilding. The closest thing to something decent was the Ra'zac, and even they are Nazgul wannabes.
The second book was more meh than anything. Contains added mary sue elves - because a generic fantasy setting cannot be without those! - and a frankly poor handled Face Heel Turn
. Also, Eragon is clearly in the closet.
The other books I haven't read, but they better bring something new to the table.