Not sure why you are quoting 6:112, 6:114 and 6:116., I have not read the context but all of them are projected toward non-believers (in case of Prophet time its pagan Arab)

The one I commented above are closer to the topic we are discussing, so here are my question if it along with explaination not clear and you care about them and wish to answer.

1) {Ye who believe! Obey Allah and His Apostle…} (Al-Anfal 8:20), we can argue about this it could have simply said Obey Allah, why it add Apostle part, there are other verse where Allah says Prophet is the role model and you will find great example in him which could mean that one should study his life. (point 4 below)

2) {Say: “If ye do love Allah, Follow me: Allah will love you and forgive you your sins …}(Al-Imran 3:31)

For this one how would you follow Prophet? for one to understand what he did and talk and behave we need to go through hadith.

3) {He who obeys the Apostle, obeys Allah…} (An-Nisaa’ 4:80)

Same how do you obey Apostle? Why limit oneself to the Quran and why not study his life and how he acted in different situations?

4) “Indeed, in the Messenger of Allah[ﷺ] is an excellent example” (33:21)

So, Prophet is a role model, one should take inspiration from his life and the wisdom and judgment he showed, again to do that one has to study hadith and sunnah.

5) “Indeed, you are a truly [a man of] outstanding character” (68:4), which justifies explanation given above in point 4 and 1

6) Similarly, Quran says to love the prophet and follow him (which requires one to study his life) how do you follow some one without knowing about the person?

“Tell them, [O Moḥammad], “If you love God, then follow me, [thereafter] God will love you and forgive you.” (Qurʾān: 3:31)

7) But no! By your Lord, they will never be ˹true˺ believers until they accept you ˹O Prophet˺ as the judge in their disputes and find no resistance within themselves against your decision and submit wholeheartedly. 4:65 .

A Similar question, not possible how Prophet solves the dispute and judge between people without studying the Prophet’s life.

8) Every ritual we do in Islam cannot be derive from Quran; for e.g Quran says we must pray but how to pray, when to pray, what do we do in pray. All of these details reach to us through Prophet and his followers.

9) Lot of Quranic verse have a context in Prophet life, for e.g verse revealed on a battle ground, on signing treating with Meccans, going for a war and so on, those contexts are also important; but if one ignore hadith will loose on lot of useful information.

10) Lastly, love of Prophet Muhammad is essential as there are numerous verses on this mentioned above, and why not it be; since Quran was revealed on the heart of Muhammad communicated through the his tounge, one naturally gets attracted to such a great person and even more to get any minute detail how he carried out his live and dealings with the people.

I mean its very normal today how people loved sports personalities, movies stars etc and biographies are written, than why not understand the person whom God chose to reveal its final message? especially he is one of the most documented person in humanity and people have spent their lives gathering this information