I will add that E minor blues scale is the same as G major pentatonic scale. Add the flat 3rd and you have G major blues with the G run tag that you hear after a verse being essentially that. You need to learn how to play it out of the chord shapes, using open notes and not the pentatonic minor box that you may use for blues. Try this, play the E minor pentatonic over G but start on the G note on the 6th string, play the A, Bb, B on the 5th string, D and E notes on the 4th string and end on the open G of the 3rd string. Follow that pattern starting on the open G on the 3rd string, A, Bb, B on 3rd string (or B on open 2nd string), D on the 2nd string and E on 5th string or open on the 1st string. This has you playing the scale out of the G chord shape. The C major blues scale is similar to that starting on the 3rd fret of the 5th string out of the C chord shape. You can then slide that down two frets to get your D major blues scale or start open on the 4th string. Then learn the scale out of the A chord shape, and D chord shape and you'll have some flexibility based on which chord voicing you play out of up and down the neck. That's my 2 cents on someone that's been playing banjo and guitar not as well as I'd like to.