Why did Eliezer add the word "today"?
Rashi: Because he had 'Kefitzas ha'Derech' - he arrived in Charan (a journey of a few weeks) the same day as he left Chevron.
Why did Eliezer see fit to tell the family all the details of the events leading up to his arrival, including Avraham's assurance that Hashem would send an angel, his prayer to Hashem and Hashem's immediate response?
Rashbam: (a) To put on a positive front; (b) to impress upon them that the entire episode was Min ha'Shamayim. 1
Why does the Torah see fit to present Eliezer's speech, even though it was basically a repetition of all that had transpired?
Bereishis Rabah 60:8, cited in Rashi: The conversation of the Avos' slaves is better than the Torah of their children. The Parshah of Eliezer is repeated at length 1 , and basic Torah laws are known only from an extra Vav. 2 Malbim
Moshav Zekenim (Pasuk 13): Also Pharaoh's dream is repeated! There, it is due to the aggrandizing of Yosef. (It also teaches that Yosef answered Pharaoh via Ru'ach ha'Kodesh
How could Eliezer say [four times] "Elokei Adoni Avraham"? Hashem does not attach his name to living people!
Refer to 31:42:1:1**.
In his Tefilah (verse 14), Eliezer said "Na'arah". Why did he say now "Almah"?
Malbim: Eliezer concealed that he intended for a girl from a poor family. Almah implies a healthy girl (from a distinguished family).
Ha'Emek Davar: He did not want to give to them room to say that she is not a Na'arah. 1 "Almah" can be also a minor.
This is like Kesuvos 40b: R. Meir holds that Na'arah is an adult (within six months after Bas Mitzvah). Rabanan disagree only when it is written Chaser (without a Hei), to include a minor. (In this entire Parshah, it is written Chaser.
Why did he say now "Im Yeshcha Na Matzli'ach
Malbim: He claimed that Avraham wanted a girl from his family; if so, Eliezer prayed for tremendous Hashgachah - the girl should be from his family, and also say like he stipulated!