Hi Brian,
Tough question, since it depends what type of trading direction you want to go in. I have been where you are now, and am still learning, but here is what I am thinking so far.
C++ has a steep, long, learning curve. I think you really have to love that to do it well. Of course, if you get a book on the subject, and you can get through it without dozing off (I couldn't), then after some practice, a course might be good.
Amazon has some good books on building models is C++ and other basic C++ books. Do a search there, there is some very valuable information.
Also, you do need to read the basics, in my opinion, like Market Wizards and New Market Wizards, which I am sure you have done by now. It seems you want to develop and trade systems, so I found an AWESOME book in Van Tharp's "Trade your Way to Financial Freedom," and Jeffrey Katz' "Encyclopedia of Trading Strategies." Tharp's book I believe was just updated. There is also a new book coming in March that looks awesome..."Building Automated Trading Systems, with an intro to Visual C++.NET" by Benjamin Van Vliet. Of course, "Technical Analysis..." by John Murphy is a classic must have.
As far as learning a language to develop a system, that may be the right way, but there are lots of programs out there now that can help get you started. The way I am doing it is I am using software that is advanced but doesn't require C++ or advanced programming languages to thouroughly backtest and trade ideas. If the software, at some point, doesn't fulfill my needs, then I will probably hire or contract a programmer to help design. FOr now, these programs seem to have a lot to offer. Check out other forums and you can find out about software like Patsystems IQ Trader, Tradecision, Traders Studio, Trading Solutions, Tradestation, Apama, and on the lower end, stuff like AmiBroker, Wealth Lab, etc.
The CFA would be a 3 year (at least) journey into analysis and won't really help with trading or developing trading systems, in my opinion. That is for analysts, more of a fundamental nature. If that's what you want to do, that's great. But if you want to trade, that is a monumental task that would be nearly useless.
I hope this helps a little.