Yes, I noticed that you had said some, but your emphasis was not there. Thank you for at least admitting that not every person is in that boat you described.
The whole Body of Christ has all of the gifts or will have all of the gifts God has for it, but not every part is whole Body. Some parts are hands or fingers or toes, but while they may indeed coincide or overlap in places it is not in every place. We do not even know all of those other parts yet. The Head knows them all. So long as we subject to the Head will we not always do what He desires that we do? It is the Head that directs and concludes... not me and not you.
One baptism and one body, but many individual parts connected to the Head and subject ONLY to the Head, which is Jesus alone. The individual parts each have what is needed to accomplish their part in the Body. God does not explain it all to each of us. We are to live by faith rather that by knowledge. Knowledge will be given when God knows that it is needed. Who else knows?
And who is it, but God that is able always to see the Body as it progresses and is always able to recognize a schism if there is one? Just because a person says that he is of the Body, does not mean that he. Neither can one member say that another is not, just because of a disagreement in doctrine or belief:
"If the foot shall say, Because I am not the hand, I am not of the body; is it therefore not of the body?
And if the ear shall say, Because I am not the eye, I am not of the body; is it therefore not of the body?
If the whole body were an eye, where were the hearing? If the whole were hearing, where were the smelling?
But now hath God set the members every one of them in the body, as it hath pleased him." I Cor 12:15-18
And what is it you define as "private use"? If God is leading a person, that is scarcely for private use. You cannot say nay unless you know God better than God knows Himself. Because you cannot discern the reason for someone speaking in an unknown tongue, does not mean there is not one...
Why did Jesus speak in parables? Why did He not simply speak simple clear native language to each person? Who decided which ones would get the interpretation and which ones would not? What is the job of each person who receives a correct interpretation from God? The person knows or can know, if he asks. But can you or I receive his interpretation for another part of the Body when we have no need to know? Does not God alone determine who has such a need?
I can use what God has given me to do what He has told me to do. I do not pretend to speak for others when God has not given me their specifics. If they are to be a part of the Body of Christ, then will God not also lead them where they need to go? If they do not, that is between them and God. They may only think they are a part. God knows. Who else does?
Consider:
I Cor 14:13-14, 22 Even so ye, forasmuch as ye are zealous of spiritual gifts, seek that ye may excel to the edifying of the church. Wherefore let him that speaketh in an unknown tongue pray that he may interpret. For if I pray in an unknown tongue, my spirit prayeth, but my understanding is unfruitful.
This says that tongue talkers should pray to receive the better gift of interpretation. The former may edify the individual, but the latter edifies the church. It does not say that they should not speak in tongues at all.
I Cor 14:22 Wherefore tongues are for a sign, not to them that believe, but to them that believe not: but prophesying serveth not for them that believe not, but for them which believe.
If tongues are NOT a sign to believers, how can anyone correctly use this alone as a basis for judging whether or not a person has received the gift of the Holy Ghost?
Mark 16:17-18 And these signs shall follow them that believe; In my name shall they 1 cast out devils; 2 they shall speak with new tongues; 3 They shall take up serpents; and if 4 they drink any deadly thing, it shall not hurt them; 5 they shall lay hands on the sick, and they shall recover.
NOT every single believer shows all of these signs immediately upon receiving the Holy Ghost. Could this not be referring to the entire body of believers manifesting all of these signs rather than each individual?
What shall we do?
Acts 2:38 1 Repent 2 Be baptized 3 receive Holy Ghost
Each of these three may be necessary to the sinner coming to the Lord, but whether or not someone has done all three is God's business, not man's. A man who believes he needs to make such a judgment about someone else must be absolutely certain that it is God's will for him to do so; otherwise he should mind his own business, not God's...
Acts 4:13, 31 IF a sign that someone has received the Holy Ghost is needed, speaking the Word of God with boldness would seem to be a better sign of the Holy Ghost than speaking tongues. This still does not mean that one who does speak in tongues as God controls his tongue should stop. If you have never had God control your tongue to speak, it would best perhaps if you remain silent about it rather than to speak against it:
1Co 14:39 Wherefore, brethren, covet to prophesy, and forbid not to speak with tongues.
Matt 7:15-23 fruits of the spirit: good trees & corrupt trees are known by their fruits NOT by their gifts. Even good gifts can be and have been misused (i.e. used for man's purpose instead of God's). Men have received gifts from God but have selfishly used them to build their own kingdoms rather than to help build His kingdom as God intended.
If we disagree with something or do not understand something that a person confirms is from and of God, who are we to plunge ahead to fix it? Do know something that God does not know?
Speaking in tongues to my God is a part of my testimony. Along with my daily studying and reading of the scriptures in three human languages I speak to God daily in English, German, Spanish and in a language unknown to me. I started doing this many years ago [first sporadically in 1976 and more regularly in later years], probably before some on this forum were born to their carnal mothers.
God does answer me even when at times I have not known the question I asked. Sometimes we need to pray a prayer against which our own carnal nature would rebel. God helps us with that. Yes, He has other ways it can be done, but we must use what he has given us. What or how others do something is between them and God. How is God leading them? Why is it different than the way He leads me? The answers... are known in every case by God, but men...? Men are to live by faith. And faith is:
"...the substance of things hoped for, the evidence of things not seen." Heb 11:1
His truth is what the Holy Spirit writes in a person's heart. It will confirm what is written by His inspiration, but the writing in the heart should be the basis for our direction. You cannot cause me to deny what He has written in me.