Keyword research question - Market Samurai

First of all thank you for taking a moment to read this question. I'm new to the whole world of IM and I'm learning something every minute. But I'm a little confused and want to clarify a few things before I throw any more money at domains/sites.

My goal is to setup micro niche sites focused on specific products and monatize the site using Adsense ads and mixing in some Amazon ads as well.

I've done a lot of research using both Market Samurai and Google Keyword Tool and have one specific niche I was looking at. At first glance the niche looked really good to me. But the more I studied it the more I started questioning if it was actually as good as I was thinking.

The top keyword, which is the broad keyword is getting the following results.

Global broad - 27,100
Global exact - 4,400
MarketSam - Searches (exact) - 145
SEOT - 61
AWCPC - $2.80
AWV - $25.20
SEOV - $170.12

I'm including those extra numbers in there because I was keeping those in mind while searching.

A more specific keyword in that niche has the following:

Global broad - 1,600
Global exact - 480
MarketSam - Searches (exact) - 16
SEOT - 7
AWCPC - $2.19
AWV - $0
SEOV - $14.52

I want the niche site to start bringing in some cash each month and I'm not looking for something big. This is more experimenting with how it all works. So if it brings in $20 a month or more, I'm ok with that.

So if you were looking for a micro niche, does this fit in a good or bad result for you? When you're researching, what numbers are you targeting or should I be targeting?

And finally one last question. When looking at the SEO competition on these keywords, I'm finding that none of the keywords have any competition by any other micro niche sites. The competition in the top 10 results are all either shopping sites like Amazon, Target, etc or Large Niche sites like for example Kitchensource.com.

Would I be crazy to go against those types of sites for specific keywords or are those easy sites to outrank on specific keywords? I know that in the Market Samurai video tutorials they show you that in their results, the sites that are 'red' are high competition and that you want 'green' colored sites for competition. But typically when I see green sites, those are micro niche sites, and they are usually well done or don't look like I could out rank them very easily.

It's 2 long winded questions, but I hope someone can make it a little clearer for me. Thanks in advance!