About the pommel on the menorah: I couldn't find the commentary about which fruit / flower it was supposed to represent. Was it the pomegranate?
One of your first questions is, "was it the pomegranate?". To this, I would like to point out the following:
In Shemos 25, G-d instructs Moshe Rabbeinu to let the people build the Mishkan (Tabernacle). In verse 33 is states:
three cups made like almonds, with a bulb and a flower in one branch; and three cups made like almonds in the other branch, with a bulb and a flower: so in the six branches that come out of the candlestick.
The Ibn Ezra on this pasuk (verse) explains the meaning of the word מְֽשֻׁקָּדִ֞ים (Meshukadim) found in verse 33. מְֽשֻׁקָּדִ֞ים is namely used as "almond blossoms" in shape of almonds:
THREE CUPS. The Gaon says that meshukkadim (almond blossoms) means in the shape of almonds. However, the word meshukkadim really is related to the word li-shekod (attached)256 in Attached daily at my gates (Prov. 8:34).257
A similair idea can be found in the commentary of the Minchat Shai:
שלשה גבעים משקדים. זה לבדו בגעיא בספרים כ"י וגם בדפוסים ישנים וכן בפ' ויקהל:
The Rambam (Maimonides), in his Mishneh Torah; Hilchos Beis Habechirah (chapter 3:1-2) writes:
The Menorah's shape is described explicitly in the Torah, and there were four cups, two knobs, and two flowers on the stem as it says "and on the Menorah there were four cups, decorated with its knobs and its flowers." There was a third flower near the leg as it says "from its leg to its flower." It also had three legs and three more knobs on the stem where the six branches came out, three on each side. There were three cups, a flower, and a knob on each branch and all of them were made like almonds.
See also the commentary of the Ma'asei LaMelekh on this halacha, where he discusses the concept of the flowers/cups being in the shape of meshukkadim.
Similary, a few chapters later, the Torah explains (Shemos 37:19):
Three bowls made after the fashion of almonds in one branch, a bulb and a flower; and three bowls made like almonds in another branch, a bulb and a flower: so throughout the six branches going out of the candlestick.
However, I found a different opinion on what it looked like, based on the translation of the Targum Yonasan:
Three embossed cups with their figurations on one branch, with the apple and lily, and three embossed cups with their figurations on the other branch, with the apple and lily; so the six branches which proceeded from the candelabrum.
See this page for more pictures, also old pictures, on what the Menora (should) looked like. But please bear in mind what Harel13 mentions in his comment.
Hope this helps!