I'm really new to RC planes as well and did find out today that you do need 2-3 degrees of down angle. I was told today by someone watching my plane that I probably need even a little more than that, especially since my motor seems to be way more powerful than needed (but only if I want to fly with a higher throttle, if I'm OK with 1/2 stick or so then I don't need to add in the down angle. So I with a more powerful motor it is even more important.