Ubermuk
Sticky & Sweet
A lot of Ash's bird Pokemon tend to suffer. They usually have an okay-ish battle run, but they tend to fail to develop them personality wise and often keep them out of the interaction scenes.
BW and XY subverted it for a while by giving both birds goofier personalities, but inevitably when the bird curse couldn't demote and genericify them, the usual evolution did. SM didn't give Ash or any main character the regional bird at all, though ironically the more minor appearances of the Pikipek line arguably had more personality than some of the main birds.
I still wish Ash had caught a Pikipek in Sun and Moon and evolved it into Toucannon. I love that bird and since Rowlet was a complete waste of space Ash kinda deserved a different Flying type.