What are the strongest apologetic arguments in defense of the veracity of the doctrine of Intercession of Saints?

The strongest apologetic I've ever read for a general belief in miracles was in Orthodoxy, Chapter 12

Which I believe may be summarized as "I believe in miracles because they happen"

Chesterton writes:

Somehow or other an extraordinary idea has arisen that the disbelievers in miracles consider them coldly and fairly, while believers in miracles accept them only in connection with some dogma. The fact is quite the other way. The believers in miracles accept them (rightly or wrongly) because they have evidence for them. The disbelievers in miracles deny them (rightly or wrongly) because they have a doctrine against them.

St Augustine says that the insufficient evidence for them happening after the fact is no reason not to believe in them. They're often local miracles.

even now miracles are wrought in the name of Christ, whether by His sacraments or by the prayers or relics of His saints; but they are not so brilliant and conspicuous as to cause them to be published with such glory as accompanied the former miracles. For the canon of the sacred writings, which behooved to be closed, causes those to be everywhere recited, and to sink into the memory of all the congregations; but these modern miracles are scarcely known even to the whole population in the midst of which they are wrought, and at the best are confined to one spot. For frequently they are known only to a very few persons, while all the rest are ignorant of them, especially if the state is a large one; and when they are reported to other persons in other localities, there is no sufficient authority to give them prompt and unwavering credence, although they are reported to the faithful by the faithful.

God, who surely respects our freewill, appears to be pleased to work though His saints and heal in a way that doesn't smash our ability to freely accept Him in the way that a voice from Heaven saying "this is my beloved Son, listen to Him" might be apt to.

St. Augustine then goes on to detail 20 miracles most of which were attributed to St. Stephen or another Martyr's intercession.

I think it is a hit or miss practice, depending on if the saints are soul sleeping in heaven or not.

On the positive side, I would argue on the lines of an angelic prayer chain of sorts.

We know that the angels rejoice over one person who is repentant on the earth (Luke 15:17). The book of Revelation states: "The smoke of the incense, together with the prayers of God's people, went up before God from the angel's hand." (Revelation 8:4)

We also know that some of the saints in heaven are aware of what transpires on the earth. And they also communicate their prayer thoughts to God. (Revelation 6:10)

Some of the saints, appeared in their glorified bodies for a brief period of time at the death of Jesus. (Matthew 27:53) So, it's possible that some of them (e.g. Mary, etc.) could be given special angelic assignments. At the very least, perhaps their guardian angels from their terrestrial days might be sent on assignment to go back to earth to make brief appearances. (Acts 12:15)

However, if the saints in heaven are primarily occupied with being intercessors, there were lots of saints in heaven from the Old Covenant times that could have been appealed to by the New Testament writers. In the Epistle of James it states that "the fervent prayers of the righteous avail much." (James 5:16) I suspect that passage is a reference to the saints that have not yet died. But, if it isn't, there are lots of righteous saints in heaven that could be invoked. At any rate, I think it's a hit or miss practice, depending on if the saints are soul sleeping in heaven or not.