I now work full time writing ESL materials. Do you want to hear my words of wisdom? No, of course you don't, and I can't say I blame you. But there they are anyway...
I'm sure your games are great, but "I have these activities. Will they sell?" may not be the best way to look at it. A better way might be "I have this ability to write stuff that's OK. What can I do with it that that's most likely to go somewhere?" Don't focus too much on individual pieces of work. I think making that mistake made it take longer for me to be able to quit classroom teaching, which I was finding unacceptably badly paid.