One of the major challenges facing improvising guitarists is playing with rhythmic variation. On piano, for instance, the physical mechanism for playing different rhythms doesn't change from rhythm to rhythm, on guitar, it often requires an exponential increase in skill.

Having the ability to play different rhythms will make your solos more varied, and therefore, interesting. Playing solos that are more interesting means playing more gigs. More gigs... you get the idea.

Okay. Let's get some mad skills. Practice the following scale with both rhythms. The triplets are definitely more demanding, no? The triplets are definitely more demanding, no?

To get the full complement of possibilites, play the exercise modally—make D the starting note (quarter note) with E-F-G as the triplet, etc.

Now try the parallel minor 7 arpeggios, which are demanding enough in the first place. But as with most things, the way to meet the demand is practice. Slowly. With a metronome