I am an OG Fox Labs owner, with an Orange TKL that I still hold dearly in my collection, though my tastes and preferences have changed.
I think the originality and simplicity of the synergy between the name and design language was the beauty in the Orange, Time, and Leaf. The name of the board was very clearly represented in the weight/accent design. Never was there a need to put the Fox name in logo or text on those.
The key logo puts the Fox name on the board where it doesn't need it, and previous boards didn't either. Other "brands" are too concerned with putting their name in a very obvious place and it makes the keyboard feel less premium, IMO. I have a lot of respect for senter/runninghack, but this direction is not in line with what I have come to expect from them.
Overall/In general, I like the F(x) logo. The fox-key logo looks unfinished and doesn't show much thought or design. The Kanji logo risks blending in with other designs that I've seen in the past, and comes off as a bit of an easy out.
Edit: Saw the plate cutouts logo version and actually much prefer this over the current key design. I shortened up the fangs on the F, and it doesn't look so disproportionate. Also, keeping it in this sideways orientation makes it less obvious and glaring that you are looking at a giant letter F. Also, the segments/cutouts are very reminiscent of the Orange and Leaf designs with negative space.