I guess everyone has different tolerance levels but coin noise in shul does not bother me that much.
But I do have other pet peeves concerning rudeness and insensitivity to a shul holiness.
I’ll mention three: Not returning s’farim to the shelves; leaving your nasty dirty tissues on the table (even for a moment); bringing or wearing your coat in shul. You would hopefully not do any of these things in your own home; let alone in G-d’s home.