I use Ubuntu 16.10 on a 2011/2012 i3 desktop, which was average by then, not top of the bill. To me it seems like 16.04 is a lot slower than 14.04, and I regret

I use Ubuntu 16.10 on a 2011/2012 i3 desktop, which was average by then, not top of the bill. To me it seems like 16.04 is a lot slower than 14.04, and I regret upgrading. Same with a Lenovo Flex laptop - it has only 2GB RAM. Since 16.04 it has performance problems. Running Firefox with Javascript is too much, or two apps at the same time grinds it to a halt.