Sorry for coming in on the middle here, but I read from the beginning.
As to Torah sources for the BBT, IINM a cursory reading of the Ramban in the beginning of Bereishis looks like he can mean the BBT. Look and CMIIW. Though he himself says a few verses later that the six days were six days of 24 hours, so he would have to hold that the world was created as is.
As to the Deceitful G-d argument, the traditional answer would be that if modern science would discover that nothing is more than 6000 years old, it would lessen confusion regarding the truth of the Torah to a degree that bechirah wouldn't exist , thereby destroying the purpose of the world.
And with regards to Torah sources for the Old World, the Abarbanel in Bereishis quotes a Rambam in Moreh who he explains as saying that the six days were six steps, not 24 hour days.
But regarding what you said about Korbanos, nothing personal @noturbizness, but you couldn't be more wrong. See Ramban Vayikra 1:9 for two explanations of ריח ניחוח, one pshat and one according to the kabbalah. If you believe that the Torah will always be true, the Torah says לדורותיכם,which Chazal explain to mean FOREVER.To look at the Korbanos like modern science looks at Aztec human sacrifice is a chillul Hashem IMO.
(Although if you look at that Ramban you'll see he brings a Rambam who explains Korbanos kind of the way you were saying, that it had to do with the mindset of the world at the time, see the Ramban's rebuttal. Pretty strong.)