Just to weigh in on the drinks...
Depending on the girl it can start an interaction on a positive, but if that's your go-to opener with women you're going to end up spending a lot of money if you do this with any regularity. It's also true that it's not going to display all the best qualities you want it to - yeah, maybe she'll think this guy is a gentleman and has money, but it also runs the risk of implying the willingness to pay for a woman's time. Maybe not at a restaurant since you're leaving it in the girls' hands whether to make an approach or not, but generally speaking.
There are a lot of girls out there who will quite willingly flirt with a guy for free drinks and all you end up doing is massaging their ego. If it's your average girl it can probably go down pretty well, but if she's hot, forget about it - she's going to have guys coming out the wazoo trying to buy her drinks all the time. It's not going to set you apart and you run the risk of being seen as "just another guy" saying "please spend time to me, I'll even buy you a drink if you'll grace me with your presence" or however it's going to come across. If you're doing it just because you're a nice guy then fair enough, it's charity, but probably better to give to Amnesty International or something.
Bottom line is, I don't think it's the worst, but it's not exactly the best either. If it feels right, okay fine, don't be a cheapskate, but if you just want to talk to the girl? Just talk to her - no need to fork out anything for it, she's only human.