Again I applaud your approach to languages, both natural and constructed, but that approach is something that can only be applied to a person such as yourself who has been openly exposed to language before adolescence. I don't know if you know of this concept, but it's a relatively well known one in all of language studies: the older you get, the chances of you becoming fluent in a language plummets after around 10 years of age, and your chances of fluency reach lower than 10% by around 18 years of age. If you learn a language in between 2 months and 10 years of age, your chances of learning other languages is extended past that 10-year dead line and can last well into your 30's.
You caught onto French at 8, which is a bit late but still well within that time frame. With your threshhold expanded, you were equally able to catch on to Spanish, Italian, Arabic and Russian. The only exposure I ever got was two years of German from an American public school at the age of 14, so the odds are a little stacked against me. Thus I need to use different tactics in order to learn a language.
I live in a backwards society that refuses to give any decent education towards language. No joke, the parents of an elementary school want the Chinese immersion program shut down because they think that the teachers will spread communist propaganda to the children who take it. I guess my point is that I live in a completely different environment than you, and will have to use different methods for language learning. I think that eventually I will look at Valyrian again, but for the time being I'm going to put my nose to the grindstone and gain fluency in Dothraki.