Yes. I am willing to upgrade to Bootstrap 4. I am not sure why you are not motivated enough, but I am super excited. Here are the reasons :
Bootstrap now uses Sass instead of LESS. This means we, the Sass lovers, have a reason to rejoice and not to forget Bootstrap now runs faster than ever thanks to Libsass (the C implementation of the traditional Ruby Sass).
The second thing I liked the most is the support for Flexbox. Now you have the option to choose Flexbox based grid system and honestly this is the future.
All the JavaScript plugins have been rewritten to support ES6. This means you have better plugin support in Bootstrap 4 and can take advantage of the new ES6 features.
I also noted that responsive typography is way easier in Bootstrap 4. This is because the new Bootstrap has moved from pixels to rem and em units, which is a good thing.
As I speculated earlier, no more IE8 support. Hurray!!