Traffic stats: https://freevps.us/traffic.pdf Right now, it will make $85/month if all slots are filled. Is that good or could I do better?
I think you are doing very well- so congrats you have a great niche. You could try an get some more private advertisers from VPS providers for a per month fee.
Thats it... Just $85; If thats all you expect thats all you will get. I hate to be harsh but you can do WAY better. WHY stop at 85? I can say that easily if you monitize this right you can get $1000 per month from a forum.