Would Botox and lip fillers be best for a gummy smile with thin, uneven lips? Can they be done at the same time? (photos)

Thank you for sharing your question and photographs. Though your pictures do not demonstrate a gummy smile, Botox can be used to lower the upper lip to increase coverage of the upper teeth.  That said I would recommend you first seek use of a thicker hyaluronic acid dermal filler, such as Juvederm Ultra Plus, to achieve your desired increase in lip size and then assess your mouth appearance.  Oftentimes with the added volume to the lips this will improve any subtle gum show.  

First off, while your lips are somewhat thin, I do not believe you have a gummy smile (from your photos). I would first try lip augmentation with filler like Juvederm ultra plus. If you like the look, then you may want to consider fat transfer, as it is more permanent. Be sure to consult with a board certified plastic surgeon. Good luck!