>> Once you get the hang of it you can make peoples days genuinely better effortlessly, by just saying the positive thing that you're thinking.

>> "How are you today" → "Better, now you're here" -- Isn't cheesy, if you mean it.

> To me that's super creepy. It's like a cheap pickup line. It's only something I'd say to someone I'd been dating a while.

Really, if the person actually means it? I think that's the key point.

I think that particular line would come off as creepy pickup line if it came from a stranger, who couldn't possibly mean it except in the most superficial way. I don't think it would come off that way if your relationship with the person is such that it's plausibly true and they don't overuse it.

On that last point, if you actually want to do something like this, I feel like you'd have to have familiar and confidence to use hundreds of phrases like that, for different situations. I'm reminded of an anecdote I read about Ronald Reagan: he was apparently known as being good with little quips and jokes. He apparently spent a huge amount of time working on them so he'd have something ready at any given time.

Full disclosure: I'm bad at complements and do none of this stuff.