Remember, you can check the full document Paschale Solemnitatis on this site, among many on the internet.
85. The readings from Sacred Scripture constitute the second part of the Vigil. They give an account of the outstanding deeds of the history of salvation, which the faithful are helped to meditate calmly upon by the singing of the responsorial psalm, by a silent pause, and by the celebrant’s prayer.
We know this pattern well. The Easter Vigil Psalms are also among the best texts we have to draw upon. Note the importance of silence after the Psalm. I would certainly advocate after the reading and before the Psalm as well.
The restored “Order” of the Vigil has seven readings from the Old Testament chosen from the Law and the Prophets, which are generally in use according to the most ancient tradition of East and West, and two readings from the New Testament, namely, from the Apostle and from the Gospel. Thus the Church, “beginning with Moses and all the Prophets” explains Christ’s paschal mystery. (Lk 24:27; cf. Lk 24:44-45) Consequently wherever this is possible, all the readings should be read in order that the character of the Easter Vigil, which demands the time necessary, be respected at all costs.
So the question is put to us: is it possible to utilize all the readings? If so, we should do them “at all costs.”
Creation and Exodus explain and illustrate the basis of the Paschal Mystery. I think Genesis 22 is difficult–symbolic of course, but demanding much of the modern sensibility that human life would be subject to what is presented as a capricious request.
A priest friend and I had a discussion in which he suggested the prophets are less necessary for the Vigil. When I put myself into his argument, it occurred to me that readings IV through VII are more telling than showing. In other words, after the drama of escape from slavery and the canticle of celebration, it can seem a letdown, despite the rich imagery of love, water, and even heavenly bodies.
I didn’t waver in my own commitment to all nine readings, but I had to consider more deeply to what I was attached.
Where, however, pastoral conditions require that the number of readings be reduced, there should be at least three readings from the Old Testament, taken from the Law and the Prophets; and the reading from Exodus chapter 14 with its canticle must never be omitted. (Cf. Roman Missal, The Easter Vigil, 21)
And the three readings are one of the two passages from Isaiah (preferably 54:5-4) and Creation. I don’t think “pastoral conditions” equates to the personal preference of liturgical leadership. But approach that matter carefully.