I've not raised Lionheads, but I understand that the pink markings you see on the sides of the darker kits are a sign that these are double-maned rabbits. This lighter pattern should disappear in a few days, so you may want to mark down which kits had the light sides.
As to the genetics, each rabbit gets one copy of each trait from each parent. Black is a recessive non-agouti self color, coded with lower case letters to show it is recessive--'aa'. Black is dominant over chocolate, so it gets a capital letter, and since you only need one copy for the trait to show, we don't know what the other copy in the pair, so a dash goes in the second place--'B_'. Black could be a full-color dominant gene, which means both the dark and yellowish pigment factories are open for business for whichever color is needed, 'C_', or it could be a self chinchilla. Chin shuts down the yellow factories, but keeps the dark pigment factories open, so a non-agouti chinchilla c(chd)_ looks just like a non-agouti full-color. A rabbit with two sable genes, 'c(chl) c(chl)' is called a seal, which can also look like a dusty black (they say to look at the foot pads, blacks have gray pads, seals more chocolate, although pen dirt can sure tint that.) So I don't know which one it would be, a pedigree would help to see what colors are in the background. Black is a dominant 'dense' color, not dilute blue, so it gets 'D_'.
Now the 'E' color extension gene could also be tricky. Normal black is normal extension 'E', so that would be 'E_'. BUT, a rabbit with two steel genes 'E(S) E(S)', also called a 'supersteel', would also look black. A rabbit with dominant black 'E(D)' could be an agouti, and still look like a self black. The other more recessive options are harlequin and non-extension orange/tortoiseshell, neither of which are an option here. However, since there is a tortoiseshell kit, we know mama must carry a recessive 'e'. My guess would be the normal extension E with the recessive e, 'Ee'.
The buck is harder for me. His face is chocolate-based, so he's a recessive 'bb' for that. The body color is so washed out, that I guess he could be a lilac tort, the dilute of a chocolate tort, which would be non-agouti 'aa', non-black 'bb', full color 'C_', dilute 'dd' and non-extension (yellow) 'ee'. It seems like the back feet are also shaded lilac/chocolate, as opposed to a sable based color that would be lighter at the feet.
In a few days, the kits will lose their lionhead double-mane light patches, and the fur will come in, which should tell you if the dark kits are actually chocolate, or black. It's harder for me to see which with the light patches right now. The tortoiseshell looks like the points are chocolate-based, either lilac or chocolate. Post more photos in a few days!
