1)
Why does the Torah repeat what the bell was made out of, but not the pomegranates?
1.
Oznayim la'Torah #1: Because "Pa'amon Zahav" is short, whereas 'Rimon Techeiles, Argamah ve'Tola'as Shani' would have been long-winded.
2.
Oznayim la'Torah #2: It is in anticipation of the question, why the Kohen Gadol could not wear it when entering the Kodesh Kodashim on Yom Kipur, since, unlike the Choshen, the Eifod and the Tzitz, it did not contain gold. Therefore the Torah stresses that, although the Beged itself did not contain gold, it contained an accessory that did.