I have been using Vivaldi for years. It is working for me.Yes, I know; I have used Vivaldi several times.
But extra tools keep the developing team from fixing bugs; instead, more bugs are introduced.
The same applies to Libre Office; give me a more simple office suite with less functions, but with a better UI and performance.
As for a LO alternative, I do find Only office to be the best option, but not on old laptops.