There seems to be an omission of an important part in your summary. Noah is the heir of the righteousness, which is by faith, but there is a mystery involved, I will show it to all. Hebrews 11:7-8, is in the correct particular and linked order, because Noah has a covenant given to him and his seed after him, and that is to Abraham, who has the covenant with him and his seed after him.
Hebrews 11:7 By faith Noah, being warned of God of things not seen as yet, moved with fear, prepared an ark to the saving of his house; by the which he condemned the world, and became heir of the righteousness which is by faith.
8 By faith Abraham, when he was called to go out into a place which he should after receive for an inheritance, obeyed; and he went out, not knowing whither he went.
So here below in Genesis 9, is the covenant with the seed after Noah.
Genesis 9:8 And God spake unto Noah, and to his sons with him, saying,
9 AND I, BEHOLD I ESTABLISH MY COVENANT WITH YOU, and WITH YOUR SEED AFTER YOU;
10 AND WITH EVERY LIVING CREATURE THAT IS WITH YOU, of the fowl, of the cattle, and of every beast of the earth with you; from all that go out of the ark, to every beast of the earth.
11 And I will establish my covenant with you, neither shall all flesh be cut off any more by the waters of a flood; neither shall there any more be a flood TO DESTROY THE EARTH.
12 And God said, This is the token of the covenant which I make between me and you and every living creature that is with you, for perpetual generations:
13 I do set my bow in the cloud, and it shall be for a token of a covenant between me and the earth.
Here in Genesis 17, is the covenant, and it is again, with his seed after him. The covenant would be established with Isaac, THIS IS THE CRUCIAL PART, OF IN ISAAC SHALL YOUR SEED BE CALLED. ow the covenant is with Jacob, so the seed after them.
Genesis 17:19 And God said, Sarah thy wife shall bear thee a son indeed; and thou shalt call his name Isaac: and I will establish my covenant with him for an everlasting covenant, and WITH HIS SEED AFTER HIM.
Genesis 17:21 But my covenant will I establish with Isaac, which Sarah shall bear unto thee at this set time in the next year.
Genesis 21:10 Wherefore she said unto Abraham, Cast out this bondwoman and her son: for the son of this bondwoman shall not be heir with my son, even with Isaac.
11 And the thing was very grievous in Abraham's sight because of his son.
12 And God said unto Abraham, Let it not be grievous in thy sight because of the lad, and because of thy bondwoman; in all that Sarah hath said unto thee, hearken unto her voice; for IN ISAAC SHALL THY SEED BE CALLED.
Genesis 35:12 And the land which I gave Abraham and Isaac, to thee I will give it, and TO THY SEED AFTER THEE will I give the land.
So who is that seed after Noah first of all, ( not heir of the righteousness which is by faith for nothing, but because of the covenant that said, with his seed after him) So it is the children of promise, as God gave promise to Abraham, of having his son Isaac with Sarah, and in Isaac the seed is called. One of Abrahams two sins was born after the flesh and not by promise, and that one persecutes the other. Then that one is cast out to not be heir with the free. The seed starting with Noah was Christ.
Romans 9:7 Neither, because they are the seed of Abraham, are they all children: but, In Isaac shall thy seed be called.
8 That is, They which are the children of the flesh, these are not the children of God: but the children of the promise are counted for the seed.
9 For this is the word of promise, At this time will I come, and Sarah shall have a son.
10 And not only this; but when Rebecca also had conceived by one, even by our father Isaac;
11 (For the children being not yet born, neither having done any good or evil, that the purpose of God according to election might stand, not of works, but of him that calleth

12 It was said unto her, The elder shall serve the younger.
13 As it is written, Jacob have I loved, but Esau have I hated.
Galatians 3:16 Now to Abraham and his seed were the promises made. He saith not, And to
seeds, as of
many; but as of
one, And to thy seed, which is Christ.
Galatians 4:22 For it is written, that Abraham had two sons, the one by a bondmaid, the other by a freewoman.
23 But he who was of the bondwoman was born after the flesh; but he of the freewoman was by promise.
24 Which things are an allegory: for these are the two covenants; the one from the mount Sinai, which gendereth to bondage, which is Agar.
25 For this Agar is mount Sinai in Arabia, and answereth to Jerusalem which now is, and is in bondage with her children.
26 But Jerusalem which is above is free, which is the mother of us all.
27 For it is written, Rejoice, thou barren that bearest not; break forth and cry, thou that travailest not: for the desolate hath many more children than she which hath an husband.
28 Now we, brethren, as Isaac was, are the children of promise.
29 But as then he that was born after the flesh persecuted him that was born after the Spirit, even so it is now.
30 Nevertheless what saith the scripture? Cast out the bondwoman and her son: for the son of the bondwoman shall not be heir with the son of the freewoman.
31 So then, brethren, we are not children of the bondwoman, but of the free.
Noah also had another testimony, of being the heir of the righteousness which is by faith, to be saved by water. Baptism also now saves us, saved by water again, and even by that heir of the righteousness, ( the son of the one born after the flesh shall not be heir) which is by faith, and the covenant with the seed after him ( which seed is Christ.) all is the answer of a good conscience toward God by the resurrection of Jesus Christ.
1 Peter 3:18 For Christ also hath once suffered for sins, the just for the unjust, that he might bring us to God, being put to death in the flesh, but quickened by the Spirit:
19 By which also he went and preached unto the spirits in prison;
20 Which sometime were disobedient, when once the longsuffering of God waited in the days of Noah, while the ark was a preparing, wherein few, that is, eight souls were saved by water.
21 The like figure whereunto even baptism doth also now save us (not the putting away of the filth of the flesh, but the answer of a good conscience toward God,) by the resurrection of Jesus Christ:
22 Who is gone into heaven, and is on the right hand of God; angels and authorities and powers being made subject unto him.
So the part omitted, is what part Noah and Abraham are, not just people who believed in God/were given God's grace, but of the covenant God made/promises given and fulfilled in Christ...
Romans 15:8 Now I say that Jesus
Christ was a minister of the circumcision for the truth of God, to confirm the
promises made unto the fathers: