Vierling has started to hit the past few games and we do know that he might have needed some AAA time. We don't "know" him as a bad player. We know him as a guy who played well in a small sample size last year and poorly this year in an even smaller sample. While also having good advanced metrics on exit velocity which suggests improvement is very possible.
We also know Quinn was walking more in AAA so could be useful in a limited role on his stronger platoon side while also providing late inning defense and pinch running off the bench.
We know Moniak played well in Spring Training. We don't know yet whether he can take that into the regular season but it is possible.
We know Kingery has been a decent bat in the past and is now healthy.
We know Herrera was a positive WAR player last year and is again this year with a .773 OPS. He is frustrating but is hitting better than most of the 6 named in that article.
The cupboard is not bare in CF even if none of the options is that good in the long run or even in any non-platoon role. There just is not a reason to make a trade for a marginal improvement over what we have because what we have is not awful.
This chart from BR is kind of fun. Pick PHI in the team highlight drop down and it shows relative rankings. SS is our weakest spot. LF is as bad as CF. The Braves are worse at each OF spot though. We did shore up DH this offseason....