I agree with this, for good Minesweeper players (my record on expert is around 55 seconds) a rate limit of 3 per second is low enough that it feels frustrating and glitchy. I think I averaged approximately 5 clicks/second on vanilla Minesweeper, but presumably with higher peaks. I imagine at launch you're getting more curious first-time players, but your community would likely gravitate towards more experienced players over time.

A simple suggestion to encourage more fair matchmaking without building a big system for it is to have separate Beginner, Intermediate, and Advanced boards, and let players self-select.

I'm not that fast, but I often ran into the rate limit in situations where e.g. I know where the next handful of flags are, and I click in bursts.

>The rate limit is extremely low for good minesweeper players.

This, I'm not good at minesweeper, but I've watch people who are and they generally clear a board before I even realize what's going on. I suppose it's a bit like NERTS, the multiple player solitaire, if you aren't that great at immediately recognizing solitaire moves, someone else beats you too them. I can play it with people I know but when I play with randoms that play all the time, I quickly lose.