I would recommend 1/5 Nuevo (Star St, Wan Chai) - we went this weekend and had a nice romantic dinner there. We were most impressed with their food, service, atmosphere etc.
We had their tasting menu which was delicious and thought it was a very reasonably priced at $198 pp (check it out here on their website - Elite Concepts)
There's also a wine pairing course with the tasting menu which we thought was okay (but next time might just end up ordering wine from the menu)
It's probably safer to book a table if you're going on Friday or Saturday - we walked in at 7pm and the dining room was pretty empty, but by 7:30pm the place was packed!
Mr. Poppalicious and I will definitely be going back!
the brunch club in causeway bay is cozy. they have a set dinner of about 200 hkd per person. so that should leave you enough for a few drinks
i recommend la terrasse on old bailey's on the outdoor patio