Does it sound natural?

Hi, I have a question.
I wanna ask "Do You think in the near future/from now on more people will be learning Japanese?". What is the best way to ask that? I have come up with two ideas.
1. 近い将来は、日本語を勉強している人が増えているだろう/増えると思いますか。
2. これから、日本語を勉強している人が増えていくと思いますか。
Does any of these sound natural?

I think you'll need to wait for a native speaker to get a definitive answer, but I think your #2 sounds closest.
You might want to change it to

これから、日本語を勉強する人は増えていくと思いますか？
or possibly
これから、日本語の勉強をする人は増えていくと思いますか？ Its just slightly changing the emphasis, but I don't think the meaning is changed at all. (However, I am often wrong about these subtleties, so wait a bit for a confirmation or rejection of that).

近い将来 sounds a bit like you have a specific time frame in mind. (3 months? 4 months? 1 year?), rather than a more general "in the future".
Regarding は vs が it is often confusing even for people who have attempted to speak Japanese for a long time (like me). In my alternatives, I suggest は instead of が since it feels like "people who study Japanese" is the subject/topic of the sentence. が still gets your point across, but it feels like its suggesting a contrast that doesn't exist. As I say, wait for validation on that point.

近い将来/これから、日本語を勉強する人は/が増える/増えていくと思いますか。

As for the difference between は and が, it differs depending on the context (stand-alone sentence, a question in a series of questions, etc.).

は can be the contrastive marker, but が also can emphasize "learners of Japanese", as Majestic-san suggested.