the sacrifices of the animals--their burning thereof--was to have been fragrant and pleasing to God

Yes, but even better with a few spices thrown in, perhaps!

Dunno, WW, I expect the idea of the smell being pleasant to God is an overlay, a reasoning after the fact to explain an ancient rite.

I feel that the essence of sacrifice is giving up something rather than giving that thing to someone.
Effectively it's putting the sacrificed object (or deed) in a heavenly bank account, and there's similarly a hope for some interest at a later date when "what goes around comes around".

Modern-day acts of charity aren't as far removed as we may like to think.