If you're in a niche area you could try selling ads directly to relevant companies, preferably with a geographical connection
Any insight on what a reasonable amount of traffic amounts to based on your experience?
I don’t remember specifically but I feel like we probably moved off Adsense when we were around 50k uniques/mo, but for a fairly specific niche.
One idea is to investigate who advertises on similar sites and examine their traffic/rates to see where you match up.