In the following two sentences:

"After many years in which no progress was made, Tony found the first red stone. Since then, several other red stones have been found."

is it better to use "had been made" instead of "was made"? or "were found" instead "have been found"?

In the following two sentences that I wrote:

After many years in which no progress was made, Tony found the first red stone. Since then, several other red stones have been found.

is it better to use "had been made" instead of "was made"? or "were found" instead "have been found"?