Life started from simple form to more complex, so i can 't guess if humans are perfect by now or a better version to be created and replace the present one.
You don't seem to understand what evolution does.
There is no such thing as "more evolved". Evolution has been going on precisely as long with us as with everything else. Evolution is the change of a species in response to their environment.
Let's look at the crocodile.
In its environment it is the most powerful, frightening thing to ever live. It is so perfectly adapted to where it lives that the
ONLY competition it has is with other members of its species. However, if you take the crocodile population and drop it in the desert, it dies. Why? Because it evolved to be good
where it is. It exists where it does
because those are the only ones who lived to procreate.
Evolution is the sum-total of eons and eons of that kind of selection. You are made up
only of the genes of those who survived. The ones who failed, well they failed. They were not around to pass on their genes. That's why you only really see successful mutations. The ones that are a hindrance tend to get the animal with them killed off, so they don't live long enough to pass on their traits, and even if they do have
some offspring the more successful ones saturate the genepool anyway.
That's what the human brain is. It's a collection of happy "accidents"(not really an accident, but it was not exactly directed). This is because all the unhappy ones
tended to die.