Some very interesting notes here. Again, you’ll want a gemara to get most of them.
Tosafos ואם explains an interesting psychological point regarding social drinking, writing that “it is the way of people to push a person who is drunk to drink more.” This is something with which we are, regrettably, quite familiar.
Tosafos דהוי notes that you can have a proxy שליח bring your nazir korbanot, but you cannot have a proxy be a nazir on your behalf.
The gemara at the bottom of 11b to 12a is the source of a classic explanation of the Pesach Haggadah’s assertion that לבן בקש לעקור את הכל, that Lavan wished to ‘uproot everything.’ The argument, based on a midrash, goes that Lavan (with his father Betuel) tried to kill Eliezer when Eliezer came to find a wife for Yitzchak. This would have left Yitzchak unable to wed, since he wouldn’t know whether he was marrying the mother/daughter of his mekudeshes fiancee.
Aside from the obvious weakness that Eliezer was only to take a wife for Yitzchak from a certain family, Tosafos אסור points out that technically one could still marry in this situation, and the prohibition described in the gemara would be a קנס - which wouldn’t apply to Yitzchak, because he wasn’t the one who appointed the shaliach in the first place. (Although, come to think of it: How could Avraham appoint a proxy shaliach to be mekadesh a woman for Yitzchak?!)
On the use of תיבעי in place of תיקו, which we also saw in Nedarim, see the Rosh on 18b who points out that the language used in Nazir, like that in Nedarim, is unusual.
Regarding Rav, it’s odd that the gemara needs to ask for a basis for his position – why can’t we just quote the discussion from back on 5-6? Perhaps this is why Tosafos ורב explains that our problem is specifically the opposition between Rav and our mishnah.
The phrase מה נפשך is often mis-translated. נפש in Aramaic is often used to mean רצון, desire. So the translation is “What is your desire?”
Regarding the debate about a person who takes a vow of nezirus while in a cemetery, see Nedarim 4a (as noted here by R’ Akiva Eiger) on the whole question of applying בל תאחר to a Nazir.
Why should he get lashes here for taking a vow of nezirus when he is tamei? Where is the deed? The Ranshburg notes at the bottom of the page propose some very interesting ideas regarding the principle that one doesn’t receive lashes for a sin of inaction, a לאו שאין בו מעשה.