Making more advertising money

I'm having some success with optimizing advertisements on the vocabulary word game site. It's doing 2x better in revenue than the old approach.

Current adsense/revenue questions:
- URL Channels - Making them work - I just created some new URL channels that I thought encompass an entire domain. For instance: vocabulary.co.il. Yet its volume is smaller than a pre-existing custom channel called vocabulary. Possibilities: Does a URL somehow double count ads? Might we have placed this code from the vocabulary channel on other sites?

- LCPC Adsense Ads - I need to get in there and eliminate the LCPC ads. How does this work?
- Multiple Google adblocks on a page - There's some reason that you want to limit the number of blocks on a page to less than the three that Google allows. Something about improving you CPC.

- I have some space on the page that is not producing much $$$s or even customers for my other business. For instance, the T4W or T4L block on the left. Would another PPC vendor (adbrite?) be a good test there? Should I play with one more affiliates? Would an appropriate Amazon page make make a decent return? Choices:
- make the 125 x 125 ultimate vocabulary add into a skycraper. Maybe get more clicks and sales.
- make the 125 x 250 under it into an affiliate (amazon?) or PPC (adbrite?) spot?


In other news. I can now show you again why non graphic artists with limited control over the tools should NOT be allowed to set up blogs. For the all time ugly blog (which hopefully will soon be fixed), check out my blog on learning fun. It's awful but I can't seem to find out how to put in a proper banner and get rid of the puke green and annoying orange.