It would be really helpful if the Filter could exclude, or indeed include if that's what you want, maps you've already played. After many months and hundreds of maps played it's more than a little difficult trying to remember if you'd already played it or not. I can't tell you the number of times I've loaded up a map played it a few moments and realised I already played it, thought it okay but probably not worth a repeat so had to bail. I know it's a bit of a first world problem, but it would still be helpful.