1. There are two interpretations in the Midrash to Ya'akov Avinu's proclamation, "Katonti m'kol hachasadim." One view is that Ya'akov was saying, "aini k'dai," that he is unworthy of Hashem performing a miracle for him. The other view is that Ya'akov felt he was "k'dai," but that it would lead to "katonti," a diminishment of his merits. The Sifsei Tzadik explains that this machlokes revolves around the same point raised in Shabbos 53b. One of the Amoraim was miraculously given the ability to nurse his son after his wife passed away. Rav Yosef remarked at how wonderful it was that this man should merit such a miracle, but Abaye took exactly the opposite position -- how sad it is that the laws of creation should be changed on this man's account. Rav Yosef looked at the occurence of the miracle as a positive outcome; Abayei looked at the high cost to a person's "spiritual pocketbook" as a negative. Yes, the individual may be "'kdai," but the cost is still great. (The other view held that if indeed a person is "kdai" there is no cost, or the benefit far outweighs the cost.)
The Imrei Emes offers a psychological interpretation of the machlokes On the one hand, a person should feel "k'dai," that Hashem values him so much that he would even do miracles on his behalf. On the other hand, that feeling needs to be tempered by "aini k'dai," the recognition of one's own shortcomings and the acknowledgment that what Hashem does for a person is chessed, not fully earned.
2. When the messengers Ya'akov sent to his brother Eisav return, the only information they provide to Ya'akov is that his brother is on the way with a large contingent of men with him. What are Eisav's intentions? Has he forgiven Ya'akov or is he intent on a fight? Tosfos (Shabbos 12b) writes that angels can even read minds. If Tosfos is right, asks R' Yosef Shaul Nathanson in his Divrei Shaul, according to the Midrashic view that the messengers Ya'akov sent were real angels, why were they unable to provide more insight other than a recounting of the surface facts? It seems that angels are not in fact privy to people's thoughts and intentions. (Perhaps one could suggest derech derush / speculation that an angel would be so repulsed by the mind of an Eisav that he would not want to immerse in his thoughts.)
Those two were for those of you learning the daf.
3. One would not be human if one did not take pride in one's own abilities and accomplishments. We all have an ego; some a little bigger one, some a little smaller. We all too easily sometimes forget that all our accomplishments would be impossible if not for chasdei Hashem. When that happens, we need to be reminded to have a little perspective. There are two ways that can happen. The first way is for Hashem to give us a little patch to knock us down to size and remind us just how insignificant our power really is. Along comes a hurricane that floods houses and cars, takes away heat and power, and suddenly our advanced society can't even provide people with basic necessities for survival.
But there is another way as well, writes the Sefas Emes. Hashem can give and give and give, more chessed and more presents and more good news, until a person is forced to say there is no way all this good could be the result of his/her own efforts or zechuyos -- there must be a higher power up there smiling down on them. How can a person not feel small when such an overwhelming debt of gratitude is owed! This is what Ya'akov Avinu asked for. "Katonti" -- Hashem, remind me of my smallness, keep that ego in check -- but do it "M'kol hachassdim u'mkol ha'emes," through giving and giving, through boundless chessed, so that we are overwhelmed not by pain, but by feelings of gratitude.