As I notedThe Bible is like a "mirror," and if we want to see how we're supposed be and look like, we look as Scripture (scriptural mirror)! Paul's statement that "I know in part" means he only has partial knowledge of God 's Word at that time, because the other writers have yet at that time to write their part; and "that which is perfect" has to do with whatever is partial, which is the Word of God incomplete. But when the Bible was completed ("perfect") we could know the entire will and desires of God; coming face to face clearly in the mirror of the Word! The Word can now confirm Itself!
Again, when the Bible was completed, there was no more need to confirm the Word with "signs and wonders": and Christians could now see what they're supposed to look like by the Word--like the Lord Jesus (1Jo 4:17), and more so all the time as we "grow up into Him in all things" (Eph 4:15).
"Which at the first began to be spoken by the Lord, and was confirmed to us by those who heard Him . . . God also bearing witness both with signs and wonders, with various miracles, and gifts of the Holy Spirit" (Heb 2:3, 4).
James also made a comparison between a "mirror" and the Word of God:
Jas 1:22-25 "But be doers of the word, and not hearers only, deceiving yourselves. For if anyone is a hearer of the word and not a doer, he is like a man observing his natural face in a mirror; for he observes himself, goes away, and immediately forgets what kind of man he was. But he who looks into the perfect law of liberty and continues in it, and is not a forgetful hearer but a doer of the work, this one will be blessed in what he does."
I would not interpret face to face in that manner
and continued
1 Corinthians 13:8–13 (LEB) — 8 Love never ends. But if there are prophecies, they will pass away. If there are tongues, they will cease. If there is knowledge, it will pass away. 9 For we know in part and we prophesy in part, 10 but whenever the perfect comes, the partial will pass away. 11 When I was a child, I spoke like a child, I thought like a child, I reasoned like a child. When I became a man, I set aside the things of a child. 12 For now we see through a mirror indirectly, but then face to face. Now I know in part, but then I will know completely, just as I have also been completely known. 13 And now these three things remain: faith, hope, and love. But the greatest of these is love.
Third after stating these three things remain Paul states
1 Corinthians 14:1–19 (LEB) — 1 Pursue love, and strive for spiritual gifts, but especially that you may prophesy. 2 For the one who speaks in a tongue does not speak to people but to God, because no one understands, but by the Spirit he speaks mysteries. 3 But the one who prophesies speaks to people edification and encouragement and consolation. 4 The one who speaks in a tongue edifies himself, but the one who prophesies edifies the church. 5 Now I want you all to speak with tongues, but even more that you may prophesy. The one who prophesies is greater than the one who speaks with tongues, unless he interprets, in order that the church may receive edification. 6 But now, brothers, if I come to you speaking with tongues, how do I benefit you, unless I speak to you either with a revelation or with knowledge or with a prophecy or with a teaching? 7 Likewise, the inanimate things which produce a sound, whether flute or lyre, if they do not produce a distinction in the tones, how will it be known what is played on the flute or on the lyre? 8 For indeed, if the trumpet produces an indistinct sound, who will prepare for battle? 9 And so you through the tongue, unless you produce a clear message, how will it be known what is spoken? For you will be speaking into the air. 10 There are probably so many kinds of languages in the world, and none without meaning. 11 Therefore, if I do not know the meaning of the language, I will be a barbarian to the one who is speaking, and the one who is speaking will be a barbarian in my judgment. 12 In this way also you, since you are zealous of spiritual gifts, seek for the edification of the church, in order that you may abound. 13 Therefore the one who speaks in a tongue must pray that he may interpret. 14 For if I pray in a tongue, my spirit prays but my mind is unproductive. 15 Therefore what should I do? I will pray with my spirit, but I will also pray with my mind. I will sing praise with my spirit, but I will also sing praise with my mind. 16 For otherwise, if you praise in your spirit, how will the one who fills the place of the outsider say the “amen” at your thanksgiving, because he does not know what you are saying? 17 For indeed you are giving thanks well, but the other person is not edified. 18 I give thanks to God that I speak with tongues more than all of you, 19 but in the church I prefer to speak five words with my mind, in order that I may instruct other people, than ten thousand words in a tongue.
Nowhere do we see Paul saying the gifts of the Spirit will be set aside when all write their part of the bible.
This is but an assumption.
How is Paul saying praying and praising God with the Spirit is a good thing that will stop when the rest of scripture is finished ?
And personally, I doubt you can actually say we have all perfect knowledge even now.
We will, however, when we all see face to face with Christ.