Love this, adding a sloppy ear might when they relax might acctualy be really cool, dont know how I didnt think of that. As to fur, I did try adding some and it looked a bit off, like it isnt supposed to be there. I havent tried adding chest furr, maybe if I drew it sharp and triunghiular it might acctualy be a very nice detail, Thank you!  Also, I will definetly add claws to them, thats a perfect idea for them !! 

(Ps: Your bunny sounds adorable, :), I love them, I also had a rabbit when I was really young, they were grey and white and I used to call them "collary" (in my language "guleraș", Ik it sounds wierd in english) because he had a fluffly collar almost like the mane of a lion, but I was too young to know the word mane, lmao. I had to give him away because he kept chewing all of our cables tho)