The ESP Guitar Company

So I started playing guitar about 15 months ago and I was doing great up until about mid Fall of last year. I was learning songs that were at my level, but one day I started trying much harder songs that were just out of my reach, but I was oblivious to it until about the beginning of March this year. I realized my playing was growing much worse and I lost all motivation and heart for it. I tried learning a few easy solos and stuff, but none of it could really get me into it. On April 19th though, I decided to learn September by EWAF. I've been really enjoying my guitar again and I've been learning barre chords and a lot of other chords due to this song. But back to my question is, where do I go after I learn September? I've been planning on learning either Smoke on the water by Deep Purpleor Down under by Men at work, but what should I learn after I learn those two songs? If you guys could give me a list of easier songs that'll gradually build me up to an intermediate player I'd greatly appreciate it. I'm into all sorts of genres from blues to funk to metal, so have at it!