I have followed FastPath since I am using it with Mikrotik devices and I have just seen that some of the LEDE+OpenWRT developers are working these days on implementing it in their kernel.
The LEDE discussion is at:
https://forum.lede-project.org/t/qualcomm-fast-path-for-lede/4582/352
The OpenWRT patches I have seen are at:
https://github.com/gwlim/Fast-Path-LEDE-OpenWRT
And the blog post about it is at:
https://aspiregemstone.blogspot.co.il/2017/06/fast-path-for-lede.html
It would be nice to get any boost in VyOS if possible.
I am not sure to which branch of LEDE it will make it but when it will be stable I believe it could be added into VyOS.
So I am requesting that if it will be stabilized it will also be added into VyOS.