A bit light is a bit of an understatement.
If you take a Shire Horse, which is probably about 7’ tall to the head and weighs 1.2 tons. Scaled up to about 11 times, that would be around 1,600 tons.
At this mare’s weight, she’s not even as dense as styrofoam, which would still weigh about 32 tons at that scale, even if you take very lightweight foam.
She should be worried about being blown away by the next breeze coming through.
Her weight seems much lower than it should be, unless my math is wrong. At 79’ 3”, she would be about 26 times taller than the average mare. Volume (and therefore, weight) should be increasing by height ^ 3, so by a factor of around 10,000 in this case. That would mean the average mare probably weighs around 1.7lb.
Please correct me if my math is off, but I think she should always wear some heavy armor, so she doesn’t get carried away by a strong breeze or something.