depends on what your space can handle
if you can maintain your product quality at high light levels, more light will definitely yield more mass of product, but its diminishing returns. In other words, dont expect that going from 800 to 1000 umol will increase yield 20%. Also dont expect that going from 1000 to 1200 umol will yield as much as going from 800 to 1000 did. I like my stuff to be low maintenance so i usually run in the 700-800 umol at the tops.
if you live in a variable climate where it gets cold and you might need to add space heating, extra firepower in your lights on reserve is kind of a no brainer (though extreme cold (60s in your room) and high light levels causes all kind f wack shit to happen as (i believe) transpiration gets out of whack