Smile Understanding the Basics of Monetisation

Hi Guys,
I am a developer who has posted three apps to the store, all got featured for a period of time, one in 5 countries.

Ive got all the tracking and reporting SDK's installed, localised to 10 countries and now I am looking to monetise.

I tried a couple of things outside of the app store and were a waste of time (Social media etc)

For Paid apps I was thinking

Paid Reviews through Gummicube
With a weekly burst through Tapjoy -

Tapjoy Questions:

1. For a 99c app what should one pay per CPI? 50c or 1.00?
2. Just run with Mobile and exclude PC
3. Split test a couple of ads for the same region (just like you do on Google Adwords)
4. Best format for Creative, Full Screen Banners or Marketplace ads?

Are there any other decent platforms for CPI for Paid apps? The only other one I can think of is Feature Points.

Now my free versions

Can someone in simple terms explain how this process works, yes I know I must have been living under a rock!

1. My two free versions are in the Utilities Category. Both have 3 IAP's each.

I have Revmob and Chartboost and Flurry SDK loaded up. I only get 1,000 installs per week.

So I have an ad budget of $200-500 per day.

So if I spend 200 per day, how many visitors should I expect and what is the best network or method, there is so many CPC, CPM, CPI.

I can see how the maths stacks up if I buy say 200 x $1 per install per day and then just reply on eCPM from Revmob to get my money back? Then hope to generate IAP for the Lifetime value of user? Is this how this Free game works these days.

I here of people getting $3-8 CPI through Revmob etc, is this really happening.

Happy to scale the $ but from experience with some other 'so called' sure bet marketing idea's like social, which returned $0.

Lots of questions but hopefully a good conversation.

Getting featured was easy in my opinion, monetisation is the more difficult aspect.