Although there are many different aspects to playing a guitar, ultimately it's the sounds produced that matter. You can be fast and know lots of tricks, but if it isn't pleasing to the ear....who cares ? Granted, one man's music is another man's noise, but everyone has the sounds they enjoy.
Personally, I believe to truly be a good soloist, one should strive to achieve a level of playing that will allow them to play a solo by first hearing it in their head and having it flow through the fingers. Obviously, this doesn't mean the student doesn't have to learn the fundamentals of music first, but ultimately the player shouldn't have to 'think through' every note of a solo.
One of the single best techniques to help yourself achieve this level of playing, is to sing or hum the notes of scales as you play them. Start off with a simple major scale, and playing slowly, sing or hum the notes of the scale as you play it.
Next, start humming a simple melody and then start trying to play the melody on your guitar. It might not be easy at first, but the more you practice, the easier it becomes. After you've become somewhat proficient, play a simple chord progression from the computer or whatever recorder etc. that you may have, and sing or hum a solo against it and try and match the notes on your guitar.
Start off with very simple melodies at first, at a very slow tempo also. After you get some experience, you'll be amazed at how the guitar can become an extension of what you hear in your head.