hiding brown leather sofas

[Iggly]

While they're practical with two small DC's I don't like them anymore.

Would it look naff if I covered them with throws and cushions...?

Nope, I think it would look like real life Throws can be a bit of a pain to keep in place, but I'd definitely recommend breaking it up with cushions.

If your back and seat cushions aren't fixed, you might even be able to get some removable (washable!!!) covers made for them in a fabric that complements the leather fixed upholstery, while reducing the brown-leatheriness of the look.