It seems that a Bosis L'dovor Ha'osur VHa'mutar is permitted only if the value of the Mutar is more than the Osur, then why by Dovid Hamelech was it allowed to be Mitaltel him through an Eesah? Is this more valuble than Dovid Hamelech?
In answer to your question, considering that a corpse (irrespective of who it was) is Asur be'Hana'ah, anything (even a loaf of bread - it doesn't say 'Isah') is more valuable than a Meis.
The truth of the matter is however, that the Din in question has nothing to do with 'Basis le'Davar ha'Asur ve'ha'Mutar', since here you are carrying the Basis on account of the thing that you put on it, which ordinarily, ought not to be permitted. Chazal permitted it only in the case of a corpse, because of Kavod ha'Meis (so as not to leave it in the sun).
R. Eliezer Chrysler