Question about the value of games?

Yes and no, maybe. Prolly not.

From what I understood if it gets bundled at a later point, it won't affect your previous giveaways. Though I think if the game drops from a base price of, let's say 60$ to 20$, it will indeed affect your level. (note - BASE price, not limited-time discounts)

It will only affect if game will get bundled before your giveaway ends (not starts, but ends). And it might not happen immediately, since it takes time to add game on a bundle list.