Save all the installed packages shown by /var/log/dpkg.log in an array:

mapfile -t packages < <(grep -Po '.* install K+' /var/log/dpkg.log)

You will have no performance issues with either version, but 16.04 is the current LTS or Long Term Support version and will be supported for 5 years. 14.04 now has limited hardware, backports,...

Give This a shot.

LD_PRELOAD='/usr/$LIB/libstdc++.so.6' steam

Hope it helps.

Steam has its own built in Runtime Library. You can find more information...

Check that PRIME offloading is working

1. This is better answered in this question: https://askubuntu.com/a/1316539/253247
...

Install compizconfig-settings-manager