I just started playing the guitar last week after having played the violin for 12 years. I have a solid sense of music theory and am trying to go into blues/rock music. I've been practicing playing minor pentatonic scales all over the fretboard and wondering what other things I should practice to get better at playing solos and doing improv work. I can currently play pinball wizard and hotel california, so I've adapted quite well to playing guitar so far.
You're on the right track, keep learning solos & in addition to minor pentatonic, major pentatonic & mixolydian are very common in blues rock. Like clapton's solos in crossroads use a mix of A major & A minor pentatonic over the A blues progression, so learn/study songs & solos & have fun with it. Also playing over backing tracks & with other people as often as possible is essential for your improv
As much as I hate to state the obvious, learn the blues scale. It's extremely versitile in both genres, and it works well with the pentatonics (both major and minor) and the mixolydian.
-Guitar Gear-
1995 American Fender Strat, EMG 85 pup
Randall RH200 Head
Marshall 1960a Cab
Woods Acoustic
-Bass Gear-
Spector Legend 4 bass
Washburn Bantam bass
Hartke HA2500
Fender Bassman 410H
Play what you love, love what you play
you should also learn the moveable 'blues' chords.

dominant and minor 7ths, 9ths, and 13ths and how they are interchangeable.

it will give the ear for blues and make some real sweet sounding music.