Composing the blues is thin ice if you want it to be significant I feel. Many of the chord changes have been done, so it is certainly mroe about trying to create an interesting melody, with "different" chord changes.
As an example, the casual band im in..we play jazz funk etc..and im on keys, and we were working on a new song yesterday. Chords are my speciality, and so I do the over-all mood and structure of the song.
We wanted to do a bluesy type thing..We chose the key of D (first note I pressed when sipping my drink

) and decided to go something like this...
D9 / / / D9 / / / D9 / / / D9 / / / G13 / / / G13 / / / D9 / / / D9 / / / F#6 / / / G6 / / / D9 / / / D9 / A aug / and repeat.
Me in my wisdom never play simple chords. I always embellish. So the D9ths are normally 13ths with a 9th, or something like that. The G13ths normally have a 9th, or i play them as 6th9ths (minus the seventh or thats a 13th -6+7) and the A augmented i like to play those with a 7th.
You see? The drummer will deal with the rhythm, but the blues structure is suprinsing. Who goes to an F#!?
Good luck..I'd find it quite interesting to follow your compositions

Regards,
Daniel