Chapter 16 completes the fifth perspective of Christ's victory, and it's the shortest of the seven perspectives of Christ's return, and I think that is by design. These bowls of wrath are God's final judgment. There is nothing more for Him to say or do. In all of the previous perspectives there have been some awful things for sure, but all of them either were warnings or came with warning, because it is always God's desire for people to repent.
v1-17 - One angel after another pours out the wrath of God. In chapter sixteen there are no trumpets blasting woes which warn all which hear, and unlike the previous calamities where 1/3 of the creatures in the sea or in the heavens were destroyed, in chapter 16, the destruction is total, final & complete.
v5-7 & 15-16 are two passages that step away from the narrative to focus on God's justice and mercy.
In the first passage, and angel praises God's justice for vindicating the blood of the martyred saints and prophets.
In v15, all of the sudden the voice of Jesus rings out, reminding you not to be lulled into complacency, for He may return any moment.
As these seven bowls of wrath are poured out, John pauses three times to note that even in the midst of the awfulness, the sinners experiencing the agony were still too stubborn to repent and glorify God:
v9 - They were seared by the intense heat and they cursed the name of God, who had control over these plagues, but they refused to repent and glorify him.
v11 - People gnawed their tongues in agony and cursed the God of heaven because of their pains and their sores, but they refused to repent of what they had done.