Same, total agreement
The current Polar Bear is actually a good size/look for a Brown bear. Black Bear should be slightly smaller. I like the idea to pair it off the circles.
Polar Bear slightly larger than this and only at a higher level, higher than 4 anyway. I also like the idea of starting out more mundane and getting more grizzly later on. And then eventually with like spirit style ancient extra grizzled grizzly bears as you improve in level. Other option would be to do it by area, where it feel more sensible to pull up a white bear in an area with like some snow on the ground at least.
Same sort of thing for the all the other animals, hopefully we get a few different wolf and lion types too, but you know the bear is always a classic and a highlight.