tput is not working because it needs to know current terminal emulator from $TERM environment variable. When ~\.profile is reading, there's just no terminal emulator in use, so tput just can't produce any output.
It is possible to specify which terminal capability to use in tput by -T key. So this code will work:
LESS_TERMCAP_mb=$(tput -T ansi blink) # start ...
There isn't a standard for forcing colours.
CLICOLOR is increasingly common, and there's an attempt to standardise it too.
You can alias commands to provide the --color=auto (or equivalent) flag by default in your .bashrc, but you'll need to find the relevant flag for each command.
You are conflating two entirely separate and unrelated things: bash's prompt string (PS1) and the colours optionally used by ls.
I also like a very simple prompt with no colour codes (and I have no need for special handling of chroots), so I have just:
You'll need to change this setting in your current shell(s) and in your ~/.bashrc, ~/....