Firstly, there's no magic line that works forever - fair enough. But the whole "find 3-4 pain points" advice is bollocks if you're just guessing. You say they're losing money, cool, but that's your opinion until you prove it. And proving it makes you sound like every other agency that promises the moon and delivers a crater.
Most marketing solutions are a gamble - you're no different unless you can guarantee results, which you probably can't without lying. That doesn't mean you can't sell it, but stop pretending pain points will save you. Some prospects are already searching for what you offer, they don't need you to manufacture a problem.
Adding more pain points just gives them more reasons to argue. Instead, focus on volume - cold outreach is a numbers game. Your research is a time sink unless it's automated. Bare minimum research, maximum outreach. Let the data filter out the never-buyers.
And capacity? That's a real one - if they can't handle extra work, your solution creates more pain. But that's a problem you solve after they buy, not before. Stop overthinking the script and start sending. You'll learn more from rejections than from hypotheticals