The renewal Frontier toys are excellent.
Some things you can extract from the current Yamato designs are covers for the screw holes on the back of the thighs, molded interior of the add-on armor and a matte finish.
I don't know how Yamato would handle the excessive use of detail on the Valks. I like the Bandai approach even if it's prone to paint scratching and I'm not a big fan of the sticker sheets.
Oh, and I guess availability would not be such an issue .