I generally don't like to leave objects centered. I've tried a couple of crops (the best is probably cutting off a bit on the left and the bottom) but I felt I was removing some of the context with each attempt.
Maybe your instincts against cropping are right? IMNSHO, look at #1 again. The dark area above & to the left (ripple) creates a diagonal & plays off against the dark area above the (C) notice at the bottom right. Then there's the diagonal coming down from the upper right. It all creates a nice frame for the bubble & leads my eye around the pic.
If I were to crop it at all, maybe a small amount from the left edge. Make a couple of prints. Put one on the 'fridge & one in the bathroom. Then see which one grows on you the most over time.