Honestly, I see nothing wrong with your example. It reads quite naturally to me, and feels much less intrusive than some of the alternatives suggested in other answers here.
It's possible, I suppose, that a longer excerpt written in the same style might eventually start to feel repetitive. From just the sample, though, I'm not getting that feeling. All it's doing (at least now that you've drawn my attention to it) is showing <PERSON> as someone who tends to signal his feelings non-verbally. Which, you know, people often do. If all your characters are doing that all the time, that might be an issue, but if it's just some characters some of the time, I wouldn't worry too much.
It might be that you're simply looking at your own writing too closely, and failing to see the forest for the trees. One useful trick to return to (or at least approximate) the "new reader perspective" is simply to set your text aside for a while — a day, a week, a month, whatever works for you — and work on something else in the mean time. Once your brain has had time to forget the details of the text, pick it up and re-read it as if you were seeing it for the first time. You may find that the little things that seemed awkward or annoying before now read just fine, while you may also be able to spot other issues that you were previously blind to.
All that said, if you still find the repeated non-verbal reactions during dialogue distracting, you should consider just leaving them out. Don't replace them with anything — just drop them entirely if they're not doing anything for you.
For example, your paragraph:
Colin nodded. 487
"You're a good man, <PERSON>," he said. "I think we're gonna get along just fine. It's a pleasure to have you in my city."
could simply become:
"You're a good man, <PERSON>," <PERSON> said. "I think we're gonna get along just fine. It's a pleasure to have you in my city."
We don't really need to know that <PERSON> nodded his head, since his spoken dialogue is already doing a decent job of conveying his implicit agreement. A bit terse, maybe, but perfectly readable.
Mind you, I'm not convinced that removing this particular nod is really an improvement, since having it there feels just fine to me. But if you wanted to drop it, you could. You certainly don't need to replace it with any kind of extra gerund or adverb or "said bookism", as some have suggested here. Not that there's anything wrong with those, either, when used where they belong. But they're not needed here, and would IMO be much more of a distraction than a simple "<PERSON> nodded." 674