need help with wheels (newbie!)

hi just lowered my bmw 325i sedan and i have style 5 wheels from a e34 they are 16s and they look a little small and i dont know if i should get 17s or 18s and i dont know what offset or width to get. i want like wheels that are nice with big lips almost like deep dish but not deep dish lol. ill add an pic of car for refernce of size. i hope i attached it

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need help with wheels (newbie!)