On your OP map I believe it but you're the only one with that.. On other maps the difference is certainly bigger than 0.3s when lowering damage a lot with heavy MF focus..Difference between MF and balanced setup: my runtimes with balanced one was 17.3 s on RFL 2017. Average with MF one first set now was ~17.6 s. So, difference seems to be 0.3 s. Or at least in my case, I can't guarantee that for someone difference would really be 2-3 seconds
Those are good items of course, but the only thing on that list that I would target specifically (with loading up on MF) are facets.
EDIT: As you said, it depends on how many of those items you have of course. May be more important to others.