Modulations in an original mini suite - your insights appreciated

[Peter C]

As an intuitive composer with no formal knowledge of music theory, I mostly visualize chords and patch them together. It doesn't always work out.

When it does work, I sometimes end up with some, hopefully, interesting key modulations, like in the piece linked below.

Am(add9) / B9 / Ebm7(9) (min. 0.18 in recording)

Gbmaj7 / Cm7 (0.23)

Bmaj7 / Am9 (4.42)

I would be interested to know if and where you may have seen similar changes and if B9 to Ebm7(9) could be considered a "pivot chord" modulation. Gbmaj7 to Cm7 may seem an unlikely change but I think it concludes the descending chromatic line nicely. Bmaj7 to Am9 - that one just "happened".

Cheers