rav lachem sheves ba'har ha'zeh

 ...Rav lachem sheves ba'har ha'zeh (1:6)

Rashi comments:
רב לכם שבת – כפשוטו.
ויש מדרש: הרבה לכם גדולה ושכר על ישיבתכם בהר הזה – עשיתם משכן מנורה וכלים, קבלתם תורה, מניתם לכם סנהדרין שרי אלפים שרי מאות (ספרי דברים א׳:ו׳).

"You made a mishkan, menorah, and kelim..."   Why does Rashi single out the menorah?  Why does it deserve special mention and is not subsumed under "kelim?" 

I don't have a good answer.  Suggestions?

Another point:

Why does Rashi quote a midrash?  Why is he not satisfied with the peshuto here?  Sifsei Chachamim says Rashi is bothered by the use of "rav" instead of "dai," but he does not explain why one term is more appropriate than the other.  I wont do your homework for you -- get our a concordance and check where else "rav" is used and see what the difference between those pesukim and this one is.  Does the term "rav" apply to a measure of time? 

I would suggest that Rashi is bothered by the entire phrase.  Why not just say פְּנ֣וּ׀ וּסְע֣וּ לָכֶ֗ם etc (pasuk 7)?  Compare with Gur Aryeh in next week's parsha 3:26, Hashem's response of "rav lach" to Moshe's tefilah.  It is the phrase itself which is unnecessary, not the usage of one word vs another which bothers Rashi.

Why indeed does Hashem not simply say פְּנ֣וּ׀ וּסְע֣וּ לָכֶ֗ם -- why the need to add that they have spent too much time at Sinai?  Netziv explains that there is a lesson and tochacha (see Kli Yakar as well) here:

רב לכם שבת בהר הזה – הרי היה קשה לפניו יתברך העיכוב שלכם אפילו בהר הנבחר והנעלה, כי היה חפץ למהר להכניסכם לארץ.

Even though you were "b'har ha'ZEH," the singular mountain of Sinai, the exalted place of mattan Torah -- what could be greater than that? -- Hashem wanted you to move on and not spend more time there.  The goal is not to attain spiritual heights in a desert, but rather to get to Eretz Yisrael and build a country.