Having a second guitar to play harmonys with can turn a simple lead lick into somthing that will really hit you hard.In Flames uses harmonys alot and there solos sound amazing(although a little the majority of there solo's follows a pattern and sound similar),yet there simple.If you can record yourself,make a rhythm and a lead track,Then harmonize with it(an octave above or below,or anywhere musically relative).Keep the solo simple.When youve got it down,add short trills,slides,bends e.c.t.A simple lick played with conviction and heart will can sound like a million bucks and be very memorable.
Ive been using this mind set of keeping it simple with great results.