Soi 11 is nice and close enough and very lively.

Hotel: Hyatt Regency Sukhumvit w/ direct connection to Nana BTS. On the corner of Sukhumvit and Soi 11

Restaurant: Burapa Eastern Thai Cuisine on Soi 11 across the street from the Aloft, excellent cocktails and high end Thai food. Rez recommended.

Another restaurant in the Nana area I love is Nefertiti for middle eastern food on Soi 3/1

-David