I long for the day where I can have the same feeling on my phone.
Rooting it is straightforward, and the first thing I did was to install a firewall, and AdAway (so I get system wide ad-blocking and tracker-blocking). It's an incredible feeling that for the first time in forever I'm more in charge of what my phone does.
The only caveat is that the support from LineageOS for less popular phones isn't great (unless you get lucky!) but if it does work on your phone, absolutely go for it.
An interesting ticket [1] is to try and boot devices using an upstream kernel. This would enhance the utility of older devices, given the community fork of Ubuntu [2] is abandoning devices stuck on a Jelly Bean kernel (v3.4) without serious back-porting.
[1]https://github.com/postmarketOS/pmbootstrap/issues/12 [2]https://ubports.com/blog/ubports-blog-1/post/ubports-communi...