I'll start myself: I've been quite interested in Esperanto recently, and I am thinking of starting to actually learn the language. Esperanto is just really interesting to me, because of its history and size, compared to other conlangs. I don't believe it will become the universal world language, like once was dreamed. And I do think esperanto has quite a few shortcomings when it comes to being an international auxilliary language. The reason I want to learn it is more just for that history and culture.
Really cool concept for a future. Insterslavic is a really cool language and one of the best regional auxiliary languages I have seen. The fact that any speaker of any slavic language can understand someone speaking interslavic flawlessly is really amazing! It’s definitely on my bucket list of languages I want to learn. (Aargh too many options!!)