If you are that good with Javascript - jump on the node.js bus rather than Ruby or C#.
In terms of making more $ the first thing I would work on is salary negotiation, not necessarily skills. There are a few great salary courses on udemy that can help with asking/answer the right questions when looking for something new or even a raise.
In terms of location/salary - I would also recommend looking to freelance for companies in NY/SF as you can get a higher rate rather than central US.
Lastly - I would say to not just think in terms of $100k but in terms of products. What products/site could you build that charges $30/month (SAAS) and can get 500 signups. Just that would get $18k/month in revenue or over $200k/year. Now $30/month may sound like a lot but take a look at Basecamp (http://basecamp.com/pricing) $20 minium a month or dive into b2b saas and checkout some of the crazy #'s they charge - http://www.marketo.com/small-medium-business/pricing.php
500 clients sounds like a lot at $30 - but no matter how you do the math (10 clients $1000/each) or (100 clients $100) a product can easily pay over your $100k/year especially if you spend the next 4 years building it. Focus on getting your first paying customer within 1 month of today and just keep going hard.
"What products/site could you build that charges $30/month (SAAS) and can get 500 signups. Just that would get $18k/month in revenue [...]"
Well if that's the process then why not just up the ante and figure out how to make some absurd amount of money?
The reality is you're not going to be able to answer that question with any degree of accuracy as to make the exercise meaningful.
All you can do is put something out there that you believe has potential and gauge how profitable it is and consider the growth potential in the future.
Node.js is a section of services that will be needed now and in the future to create distributed web services/ sites, so yes node js is important to the next level of the web resources.
I believe s/he's saying if you invest the effort to learn Node (considering you already know js), you could find yourself in a significantly more marketable position in the near future (thus increasing the chances of making that 100k).
In terms of making more $ the first thing I would work on is salary negotiation, not necessarily skills. There are a few great salary courses on udemy that can help with asking/answer the right questions when looking for something new or even a raise.
In terms of location/salary - I would also recommend looking to freelance for companies in NY/SF as you can get a higher rate rather than central US.
Lastly - I would say to not just think in terms of $100k but in terms of products. What products/site could you build that charges $30/month (SAAS) and can get 500 signups. Just that would get $18k/month in revenue or over $200k/year. Now $30/month may sound like a lot but take a look at Basecamp (http://basecamp.com/pricing) $20 minium a month or dive into b2b saas and checkout some of the crazy #'s they charge - http://www.marketo.com/small-medium-business/pricing.php
500 clients sounds like a lot at $30 - but no matter how you do the math (10 clients $1000/each) or (100 clients $100) a product can easily pay over your $100k/year especially if you spend the next 4 years building it. Focus on getting your first paying customer within 1 month of today and just keep going hard.
My 2 cents :) Good Luck!