I personally have never felt the love at first site thing. It probably has a lot to do with me being a very introverted (well beyond shy into actively not being out-going) personality. Personal appearances might catch my eye, but have never made me decide that I should go after them (yes, even if it was some major celberity/model showing up nude on the doorstep letting me know they wanted me). On the other had, personal appearance/habits are sometimes off-putting enough to not consider them at all, even if otherwise they are really neat people (though honestly... I have only met a few whose habits/appearance are that far off).

For me, I do have to get to know someone and develop real feelings for them. Attraction might lead me to seek them out, but I guess I've developed a strong enough sense of detachment/aloofness (being around cats) of myself that I've never had that wildly attracted to someone level on first meeting them. Doesn't mean I'm not quite passionate... but we won't get into that ;)

Chemistry is a must. It's just there or it isn't. You can't make a relationship based on only chemistry if "the personality doesn't have the cash", but you also can't make a romantic relationship work if the chemistry isn't there either. You're on the right path. :)