what would you suggest as a way to practice getting good at improvising. Whenever I play over a chord progression - for instance C, F, then G (a generic I-IV-V), I end up "stuck" playing the same 'improvised' solo over and over. Would you work out cool sounding licks before soloing, then incorperate them? Wouldnt this change the meaning of an 'improvised' solo, since the licks are planned out? Or with time, and with practicing over chords, break out of this rut and 'feel' the chords and what I want to do around them? This aspect of guitar is difficult to know how to practice.

Try other progressions. The more interesting the progressions are the harder you have to think to make the melodies connect. Good luck.