Crepe Myrtle bonsai inspiration

This ugly picture is of a crepe myrtle I have growing in a wooden box, and is overwintering in my root cellar, where it stays between about 38 - 50 degrees F all winter.

I haven't found many examples online of crepe myrtle bonsai that I like, but here are a few that have some potential.

This Spring I removed it from its grow box and trimmed the bottom of the roots. I improved the drainage of the pot by cutting a 1" wide slot most of the length of the box, and stapled some fiberglas screen over it to keep the soil in.  I added 2-3" of new soil in the bottom, since it was a little low in the pot, and replaced it in the box.  I am hoping it will add enough girth to the trunk that I can chop the trunk next winter and begin to train it as a bonsai.  I'm tired of bringing that huge pot into the basement every winter.

I may have identified this as the 'Potomac' cultivar of Lagerstroemia indica.

For some reason it did not bloom this year, possibly resulting from our cool wet summer.  It also did not add any girth to its trunk either, which is very disappointing to me.  I think I will try keeping it in my detached garage this winter, surrounding the box with bales of straw.  This will avoid having to haul it down to the basement.