Even though you may feel that it's not your best, still a pretty good start as far as I'm concerned.
An interesting observation in how patterns are all around us in every day objects and it works for the theme.
I had the same thought as Stan about cropping out some (or maybe all) of the bottom step to balance the composition. I also wonder how a 90 degree rotation would look so that the steps are vertical in the frame. It might add something to the abstract nature of it.
Actually, while I was typing that I just had a mental image of a red rubber ball bouncing down the steps or maybe a multi-coloured slinky (with the steps in the current orientation).
If you could have managed it, I think a little quirky touch like that would really lift it and give it another point of interest.
As for picking your best shot, take a look at Ian's thread
here.
Sometimes if you're undecided, it can be a useful learning experience to talk through your possible options and put your reasoning down in writing.
p.s. If you haven't seen it, there's also a 'pictures only' thread
here.
If you also post your photo there with a link back to your thread, other 52ers will know that you've updated your thread for this week.