re: Going to downtown Houston, bar recommendations please

Yea, just go bar hop the Main St and Market Square area.

OKRA, Captain Foxhearts, Little Dipper, Honeymoon, Warrens, La Carafe, Public Services, Prohibition, Flying Saucer, Moving Sidewalk, Hearsay. There's so many varying options right there that something will hit the spot for you.

Then after you're done bar hopping, go grab a beer and some drunk food at the Conservatory food hall underneath Prohibition.

ETA - If you're looking to hook up, go to midtown. Downtown is more about drinking. Though Prohibition is usually pretty stacked and they have burlesque shows on the weekends for entertainment.