I played guitar for many years without a clue when it comes to keys, modes and music theory. Modes are a bit tricky to get your head around and in the end I just feel that if people like the sound of something I post and find a way to use it that's enough. The real fun with modes begins with modes of the melodic and harmonies minor. I might post something like that soon. Hang on I already have. I think I posted the Jazz vehicle in both Harmonic and melodic minor. If you take those loops and shift the start point that's exactly what you get.
The Jazz vehicle is a 1,4,7,3,6,2,5,1 progression ( moves in 4ths)
Assuming the progression is in the key of C minor, if you start the shifted loop from the 3rd chord ( the 7 chord) you get a Jazz vehicle in the key of B superlocrian (also called the 'altered scale as it contains all the altered notes... # and flat 5th and 9th along with the root, 3rd and flat 7th)
Given that in a Jazz context you would use that over the 5th degree chord, that would put you in the key of E.
Following so far?
I did say it was complicated.
My suggestion is always though to play around with things and see what you like the sound of.
Also experiment with shifting the start point of any of those "jazz vehicle" loops.