[Adamanta]

Aql (intelligence or reasoning) and nakl both are necessary. Just going with aql can be dangerous. As muslims we acknowledge that Allah SWT is the Most wise and the Most knowing and we have lot of shortcoming and we can never fully comprehend the wisdom of Allah SWT. Our beloved Prophet SAW is the most wise of us all for there is revelation behind his actions and words. So when it comes to the sayings of Allah SWT and the Prophet SAW, we should trust them more and simply submit to them even if our aql says the other way. So in these cases, nakal is very important.
Aql is important for it is a blessing too but completely relying on it can be dangerous.
As far as nakal of parents, see when we come to this world, we believe the woman when she says she is our mom and we believe the father to be the father. So everyone does nakal of parents here. We should not obey parents when it comes to disobedience to Allah SWT though and so we can't be too blind in such things. We should keep seeking knowledge and keep praying, "Rabbi zidni ilma", O Lord! increase me in knowledge.
We also should ask to Allah SWT for beneficial knowledge and save us from knowledge that is not beneficial.
Sorry if it confused you. Let Allah SWT grant us good understanding. Ameen
Allahu alam