Try to improve the traffic. That's the key. I know it's easier said than done, but with hard work it can be done.
Aternatives:
1. Text Link Ads:
Text Links in Sidebar, RSS feeds and end of posts. Get
PR 4, Alexa top 100k and decent Technorati Rank, then you can earn $100-150 easily every month.
2. Kontera:
This is Conetent Ads. The text will have Double line links. Design wise bad, but if your other things are not paying well, then you might want to go for this.
3. Private Ad Sales:
Recently I closed a $750 sales for my blog. This is the best way to earn money. Slowly you can do only private sales and then remove other things. But you need good traffic for this.
Note: I didn't mention CPC programs. Adsense is the best, IMO. YPN pays well but only for US publishers.