[wulf]

I would suggest that it could do with being a bit sharper; this may be a side effect of stopping down to f/22 (diffraction). DoF is a concern at macro ranges but I think you could probably open up the aperture a bit - try f/11 or f/8 and see if those are usable. That will also let you use a faster shutter speed. At 1s, you may be getting movement from the plant and water which contribute to the softness.

Contrast is okay but I think it would be worth experimenting with different angles to see if you can get your main subject (strand with air bubble) sitting against a darker bit of the background. More sharpness on the strand would also help separating it from the light green strand in the mid-ground area.

Wulf