Awesome! There are a surprising number of people interested in language in this thread :). Do you have any particular area of L2 acquisition you're interested in? I'd love to hear about it!
I'm interested in the developmental processes behind the switch from understanding via mental translation to near-native understanding. When people start out learning a new language, they tend to have to translate between the new language and their native language. For example, the German word "Vogel" and the English word "bird" both mean the same thing. An English speaker learning German will start out by translating "Vogel" to "bird" mentally, but can eventually just come to understand that "Vogel" refers to a winged, feathered creature (and even understand the German words for "winged" and "feathered" on the same level). I'd like to study the changes that occur in the brain as this transition takes place. I also have a BA in philosophy, so my interest in language is broader than just its acquisition. In philosophy, linguistic precision is absolutely necessary. One of the first things philosophers do before starting a discussion is define their terms with the intent of sticking to those exact definitions. Because of that, I have actually developed an interest in the imprecision of common language. It is absolutely fascinating to me that there are so many cultural idiosyncrasies in within any given language, but communication is usually not hampered. I'm not sure exactly how I would study this from a developmental or psychological perspective, but I think I have time to figure that out.
Awesome! Sounds really interesting. You might be interested in pragmatics/developmental pragmatics based on what you said in your second paragraph. Humans make crazy amounts of inferences all the time so that we can reduce the cost of communication (being perfectly precise is incredibly costly!). You might be interested in the so-called "tug of war" between quantity (be brief) and informativeness (say enough for your speaker to understand what you're talking about). I think Steve Levinson might have a good review of this, and ofc Grice is always good.
I probably would. As a philosophical stance, pragmatism is very attractive to me, so understanding related scientific concepts should be pretty interesting too. As it happens, that "tug of war" is a common conflict in philosophical and scientific writing. I'm sure you've probably encountered some philosophical works or scientific studies that were just plain wordy.