I do not intend this to be mean at all and I do think your photo is quite good. That being said, you are clearly very biased here. As others have pointed out, your image does not show the whole organism. Frankly, it is a worse representation of the species than the current taxon photo, which is not only clear but has the entire organism is in focus. Keep in mind that the primary purpose of a taxon photo is to make it easy for someone who is unfamiliar with the species to have something to compare their observation to. Generally you should not change a taxon photo unless the current one is subpar and the one you are replacing it is much clearer. An example of this would be Fallapion pensylvanicum. Currently I have the only observation of this species on iNaturalist, and so my photo is the taxon photo. However, my image is not very sharp and should be replaced if one that shows what the species looks like becomes available.
Again, I do think your photo is quite good and you should be proud of it, but it is not an ideal taxon photo. Unless the it is extremely clear that a photo better shows the details and gestalt than the current taxon photo of the species, the change should be discussed before being committed. This is especially true if the photo you intend to use is your own.