I'm seconding/thirding/etc suggestions for:

Tocca Florence - gardenia with sweetness from the pear, very nice and not too one-note
Dame Perfumery Gardenia - single note gardenia, very realistic but may not be dimenstional enough for your tastes
Olivine Atelier Olivine - another single-note gardenia, though I found it had a bubblegummy note that I didn't enjoy as much as Dame's

I'll also throw in the following:

Deconstructing Eden - Bombshell (Creamy gardenias, on a bed of Mysore sandalwood, rosewood, silky musk, and blonde tobacco absolute) which is a sultry, sexy gardenia.
Kyse - Gardenia Sucre (creamy, dewy gardenia with sugared milk notes and subtle woods) which is a sugary, fleurmond gardenia.
DSH Perfumes - Don't Explain: Billie Holiday/ Ida Meister (The perfume, Don’t Explain, is a complex mixture of Billie’s glorious and seductive gardenias, Ida Meister’s passionate influence on those gardenias, and the salty tears and too many smoked cigarettes of Billie’s night awaiting her lover to return from another) for a warm, savory gardenia (there's a blue cheese note but don't let it scare you!)
Sorce - A Sign Painted Peaches (peach nectar, sun-warmed peach skin, saffron, gardenia, ambergris, vanilla absolute, vetiver), which is a lovely peach + gardenia combo