Easy fix If the content is worthy of sharing with direct traffic from places like same niche forums, etc... SEO is only one source of traffic.

So... make some money with direct traffic, then reinvest that money back into SEO.

If your content is lowest bidder junk like fiverr, well, don't bother building a site.

Just reverse your process. What people want to read? Give them to read or solve their problems, then they will come again and again to your site. Continuous flow of traffic to your site is secret of adsense income.
So, start building site for people and not for adsense(NMFA). You will enjoy long term success.

When i outsource my content i always do some research on the keyword, i let the writer know what i want to see in the article, this to make sure that it is actually helpful to those seeking that information and not just some random common sense remotely related to the keyword.

So is it worth investing in 100 of those articles (doesn't have to happen in a day ofc) and then putting adsense on the site? Will i have to rank every single article with offsite SEO or will some good offsite SEO to my main site help all those articles automatically rank on their own if my main site raises in autorhity/PR etc?

Anobody? I am kinda stuck in making a descision :p

If you trace back the google's approach in recent year, lot of preference has been given to on page optimization rather than offshore optimization... Even in coming years of SEO .. Google will definitely reward the content more than the off page stuff.. If I were to be in your place, I would rather spend more money on the on page optimization rather than on off page.
I have ranked many sites in the first page of google just with the right on page optimization, with just social book marking itself in a matter of couple of weeks.. Hence for a micro site going on page is the best approach...

Whichever articles you will get it created, convert them into pdf and share it with document sharing site as well with link back to your main page, that is also working pretty good now a days.
Cheers.. Dont hesitate to reach me, if you need any more help

-No one can decide for you without income information.

-Quality is better than quantity. I do not think you need 100 articles, 30 well-research articles should be enough for start-up. The structure and layout of article are necessary, this will help to increase or decrease conversion rate.

-The budget is important, you need to prepare enough. With my experience, it needs $100-$200 per month for SEO, promotion, add more articles, hosting... Without it, you can not rank or get enough traffic for conversion.

If the content is good, UNIQUE and useful for people, they will share it themselves, so you will get A LOT more than just those 2k per month... Also, the best idea is to try ranking for a much powerful keyword and obtain those low competitive keywords by each article. So I would continue writing those articles, but change your main idea (another keyword, use H2 tags, etc.)

I’m sorry to break this to you but the 12 articles that you’re talking about might not be enough.

Even if you scale up your website to 100 articles it might still not be enough to push the ball forward.

Instead of focusing on content quantity, you might want to start with a blank slate and just focus
instead on the core needs of your target audience members.

You might want to [expand] more energy in a properly profiling members of your target audience, as far as their needs are concerned, and attack the problem that way.

Pay attention to less popular ways of phrasing certain niche phrases.

You’ll be surprised as to how lucrative these niche phrases are.

The situation’s made it all the more attractive because while the keywords are lucrative, commercially speaking, they have low levels of competition.

This gives you a tremendous competitive advantage.

You’re not reducing yourself to the all too common situation of [sniping] for the same keyword as everybody in his dog in your niche is sniping for.

I'd vote for #2. Take what you've learnt and apply it to a new niche.