I really like VueJS and I actually think it is a pretty safe choice. While it has been gaining a lot of momentum recently (especially in the Laravel community were it has become the default frontend framework), it has actually been around for well over 2 years. Evan talks about the stability of the project more here: http://blog.evanyou.me/2015/10/25/vuejs-re-introduction/
Another really important point is that Evan is able to work on this fulltime thanks to a really successful Patreon. This is super rare for a open source project but pretty much guarantees support for the project for the foreseeable future.
BTW, where you said "save" and "savely", you meant to say "safe" and "safely" ;)
It's a pretty safe choice, Evan is working on it full time and it keeps getting better and better.
A framework is useful because once you learn it, you can apply that knowledge across a wide range of projects. Not only that, but once there is intro documentation for it, the knowledge imparted can help people be several miles down the road of understanding the structure of a many projects. For this reason, the biggest thing I look for in a framework is solid canonical introductory tutorials that help someone build a solid mental model of the framework. This means that even if the number of developers is currently small, it will grow fast enough that I won't worry about hurting my ability to hire down the road.
It is especially useful if the intro tutorial teaches automated testing. Then I'm going to be less worried that tests are an afterthought rather than something that is written alongside the feature.