I like the filters for creating new games, allowing us to select opponent speed, number of games played, etc.

One small addition I would make is to allow us to choose an opponent based on number of games in progress. I have no interest in waiting for someone with 150 games in progress to cycle through all their games to get to mine. After someone accepts my game, I always look at this stat and then decide to play or abort.

This stat is meaningless. Some players with 3 games have an average move time of ove 1 day. Some players with 100 games have average move times of less than  2 hours.

Average move time is the one you should look at, if this bothers you.

Average time is not clear to me.  Is it average time to move in any game, or to move in any particular game?  In other words, if a person's average time per move is 1 hour, does that mean he makes 1 move per day in each of his 24 games?

If his average time per move is one hour, I'd like to hope for his getting to our game in that hour.

Ah, it's a little more complicated than that :)

It is the average time he takes to respond to opponents moves.

You have to understand there are things outside his contol which slows this down. For example, he moves in all his games, and logs off. If his opponents move very soon after this,  his clock starts ticking, and the average time goes up.

If he can maintain a low (say, sub 3 hour) average in spite of this, you can be fairly sure he will respond to your moves fairly quickly if you are both online.

[edit] I see your time is 2 hours 15 minutes. You can assume that someone with an average time about the same as yours respond about as quickly as you do.

Ah, ok.  So it's the average time it takes him to respond to a move in any particular game.  OK, that's more useful than I thought.  Thanks.

But now I've run into another kind of irksome behavior. When playing someone, we're exchanging moves every few minutes or once an hour or so. Then my opponent fell behind in material and now has a clearly losing position.

Now he moves in our game only once a day, but quite rapidly in his other games. What's the point? Someone with an average move of once and hour now has a handful of losing games in which he's refusing to move.  This might be reflected in Games in Progress if his habit is accumulate many of these games.