Hey thanks, glad you dug the lesson!
For the leads I used an Ibanez RG-something (don't know exact model number). String gage might be something to experiment with for getting those high notes to pop, but the general consensus there is - "the heavier the gage, the richer the tone". Using that train of thought, perhaps the lighter strings wouldn't necessarily be the answer (although nothing wrong with trying!).
Another thing I would experiment with is your amp tone. If you are finding that the high notes aren't popping, perhaps increasing the highs and presence on your amp or modeler may do the trick.
One last thing is to slow down the licks and make sure you are hitting everything cleanly and distinctly. Much of the tone comes directly from your fingers, and things can get a bit muddy if you're not playing the licks as cleanly as possible.
Hope this helps, lemme know how it goes!