The scorpion models seem different; more armored and busy. I liked the old ones better, at least for the giant ones. They looked more realistic and overall cooler. I hope you’ll consider changing them back, since they were one of my favorite assets in this game (close to the giant crabs).
I don’t mind giving the beast master companion a different look (though I’d still want the old model as an option if I played beast master). The new one looks like something out of sci-fi, while the old one had a more fantasy look. My playgroup was just talking last week about how cool the giant scorpions were.