1) Purgatory is entirely Scriptural, particularly when dealing with the total Analogy of Scripture. But to be specific, the allusion to Purgatory is unmistakable in 2 Maccabees 12, which is certainly Scripture to us Catholics, and - long story short, for now - only became "unScripture" to Protestants because of the very allusion I note here.
3) Have you never read 1 John 5:16-17? A clearer distinction between mortal and venial sin, and their obvious differences in effect, is hard to find.
5) "Mandatory" celibacy for priests and bishops is only a discipline in the Western - or Latin Rite - Catholic Church. Married priests exist in the various Eastern Rites of the Catholic Church. Only bishops are universally not allowed to be married. And this could change - though there is little likelihood of that - because no one ever said this was doctrine, it is only a discipline based on, among other things, St. Paul's"opinion" found in 1 Corinthians 7:25-39, with reference also to 7:8-9. Notice, particularly, what St. Paul has to say in verse 8! Celibacy is a gift to the Church as a whole in this vein. And these passages alone - and there are others, too - indicate that it is not "mandatory" that a bishop marry. St. Paul himself, as an Apostle, was also a bishop, yet he says plainly in 7:8 of the above text that he is single and has no intention to marry. Yet this does not disqualify him, does it?
8) You really need to define what you mean by "exclusive sainthood," before this question can even be addressed.
Also, a general observation. A few things on your list do not have massive Scriptural support in any direct sense, though there is, in these cases, still some indirect evidence. Just the same, the Catholic Church does not recognize "Sola Scriptura" as a principle, since, among other things, the statement is self-refuting. "Sola Scriptura," or "Scripture alone," can be nowhere found in the Bible, therefore, it cannot be a Biblical principle,and to insist on the point is, as I already said, to engage in a self-refuting argument.
The Catholic Church regards Sacred Tradition to be authoritative like Scripture. So does does every other Church that has a legitimate claim to being "Apostolic" in its roots, that is, the Orthodox and Oriental Orthodox Churches, along with Catholicism. Protestants need to ask themselves why this is so. Why do all of the ancient Churches which predated Protestantism and still exist today recognize Tradition along with Scripture as "authoritative"? Upon what authority did they unilaterally decide to jettison Tradition? It certainly wasn't Scriptural authority, since, as already noted, Scripture says nothing whatsoever about Scripture being the only source of authority.
Neither does plain logic or an understanding of early Christian history, since the Bible was not codified in any real sense till the end of the 4th Century, and it was well into the 2nd Century before most local churches spread throughout evangelized territory could have possibly hoped to have had a significant portion of what would later be known as the canonical books of the New Testament.
Therefore, since all still-existing Churches that predate Protestantism recognize Scripture and Tradition, it behooves Protestants to explain how, and by what authority, they had the right to fabricate a "Sola Scriptura" principle to justify the removal of Tradition.
More later tomorrow, if I can.
Though it is only a church law, celibacy shows contempt for Scripture. As cults abudantly evidence, one can say a doctrine is “based” upon a text, but that does not mean it is the result of sound exegesis. 1 Cor. 7:8,9,32-38 certainly does support celibacy, but by no means as a mandatory requirement for any class of people, let alone clergy, who were obviously expected to be married in apostolic times and forward. (1Tim. 3:1-5,12) Rather, Paul states that celibacy is a gift, (1 Cor. 7:7), and to require that all Bishop/Elder (same office) have that gift is to add to Scripture, just as the Pharisees did, “teaching for doctrines the commandments of men.” (Mk. 7:7).
As for purgatory, this (as taught by Rome) likewise lacks true Scriptural warrant, including the treasury of merit and indulgences, as it must rely on ambiguous texts which are contradicted by clear ones. The “servants” in Lk. 12:42-48 are evidenced to lost souls, with different degrees of judgment being realized in the afterlife. Yet ordinary saved souls are distinctly told that if the rapture occurred they will be “caught up together with them in the clouds, to meet Lord in the air: and so shall we ever be with the Lord.” (1 Thes. 4:17) The penitent criminal who suffered a few hours on the cross himself went that day to paradise, which is later revealed to now be the third heaven.
At the judgment seat of Christ believers are told that carnal works will be burnt up, (1 Cor. 3:11-15) but they themselves will be saved, so as by fire, which does not convey suffering an indeterminate time in purgatory, but of a man who loses everything but himself is saved, the context here being about rewards.
As 2 Maccabees, this book has offers hope for those dying in “mortal sin”, as idolaters, while the apocrypha is not worthy to be classed with Scripture, which is evidenced to be such by its power and purity, resulting in its popularity, while apocrypha remains buried in obscurity. See here for reasons why it is rejected by the revived church.
Of course, when you autocratically declare yourself infallible in a teaching, then lack of Scriptural warrant need not be a problem.