I'd suggest learning some metal songs and analyzing how they use the techniques you have been working on.
Ozzy- "No More Tears" this song uses drop-d tuning and has lots of harmonic squeals
Megadeath- "Symphony of Destruction" the riff in this song is pretty easy and sounds pretty cool
Metallica- "Fade to Black" the lead parts and solo in this song aren't too incredibly fast and they stick to the E-minor scale for the most part
Dio- "Holy Diver" I love the solo in this song and the rhythm part is fun to play
if you don't have these songs, I use Seeqpod.com to listen to songs for free
Electric: Schecter C-1, Hot-rodded strat
Acoustic: Ovation Celebrity Deluxe, Epiphone
Keep on rockin' in the free world!