I would never shoot through a glass pane, but the result is passable despite that decision. I know how skittish this species can be, so I guess you take what you can get. Eye is nice and sharp, so that's good. More depth of field would be good, but you didn't have much light to make that happen. The top of the frame feels a bit empty, so I would play around with the crop to achieve better balance.
Thanks, The bird was sitting on a metal fence post and I have tied a perch there since to see if I can get a 'paneless' shot from outside, if it comes back!
Good job through the window, but yes, hopefully your plan to go "paneless" works out. Maybe some full-body images as well if the perch looks good that way no need to crop lots. Fun backyard project!