This monday, as I started my 'song a week' routine, I came up with this lovely chord progression (listed below). It is clearly some form of E, and I could go as far as to say it's a major scale. (The chords were named with the help of an app so I committed no mistakes).
Eb-F-Bb-F-G (listed as Ebadd9) D-F-Bb-F-G (listed as Gm7/D) C#-F-Bb-F-G (listed as Bbm6/C#) C-Eb-G-Bb (listed as Cm7)
As it is evident, the first three chords vary only at the 'bass note' (?), with Eb, D and then C#. The fourth chord was an attempt to alleviate the tension and direct it to the root.
Is there a name for this type of variation? Has this scale a formal name?
When it ends, the last chord I play is a lone D7 (D-F#-C-D-A) to create unresolved tension. Should I play a Ddim7 instead, for theory purposes?