Eph 1:3-14 = The Christian Community's Spiritual Blessings in Christ
Eph 1:3 = Introductory blessing to God
Eph 1:4-14 = An Explanation of how God has blessed us in Christ
v. 4 = Blessing #1 (election in Christ)
v. 5-6 = Blessing #2 (adoption in Christ)
v. 7-10 = Blessing #3 (redemption in Christ)
v. 11-12 = Blessing #4 (our inheritance in Christ)
v. 13-14 = Blessing #5 (our sealing by the Spirit)
Anyone who attempts to delineate the structure of this passage is faced with two particularly pressing problems: 1) the phrase "in love" in v. 4; 2) the significance of the particple gnwrisas ("making known") in v. 9. Regarding the former problem, the issue is whether to connect the clause with the phrase "holy and blameless before him" or withthe verb "he predestined us" in v. 5. At this point, I tend to connect it with the verb "he predestined us." First, Paul seems to begin every major section of this passage with the preposition "in." Second, taking the phrase with Paul's statements in v.5 would create a rather nice parallel with Eph 2:4. Third (and probably most important), the phrase "in love he predestined us" is much more natural than "holy and blameless before him in love" (commentators who adopt this reading seem divided on what Paul might be conveying with this statement).
Regarding the latter problem, the issue is whether to take the participle "making known" in v. 9 with the grace God lavishes in v. 7-8 or to see Paul starting a new section in the passage. At this point, I tend to favor the first option. However, there are (in my opinion), convincing reasons for adopting the latter option. First, Paul also seems to begin a new section with a participle (proorisas) in v. 5. Second, the noun "mystery" plays a major role in the theology of this letter. It then becomes rather natural to see the revelation of this mystery to the believer as one of the spiritual blessings Paul is describing in this passage. That said, every other major section in this passage begins with the phrase "in him." Perhaps most damaging to the view that takes v. 9-10 as a new major section is the fact that Paul is describing heavenly realities (v. 3). It is true that Ephesians establishes a close link between earthly and heavenly realities. However, it is difficult to see how understanding the "mystery of Christ" (Paul probably equates the "mystery" of 1:9 with the "mystery of Christ" in Eph 3:4) could be considered a spiritual blessing for the believer.
Look out for a more detailed analysis of the structure of this passage, hopefully in the coming days:-)