I don't use Linux at the moment, but one of the things I miss most is the lack of bloatware. It's so refreshing to have just the applications you need, not some weird thing running in the background eating up your RAM.
It's hard to say what would change the most for you, as it depends a lot on what you do. I recommend installing it as a secondary OS and trying it out to see if you like it.
One of the great things about Linux is that you can find almost any information you need on the Internet, so it's pretty easy to learn how to use if you're more or less technically inclined and like to research solutions online.
Oh my god that sounds like a nightmare