No!
I l’amour Romione. They have perfect chemistry and it is obvious they are in love. Ron is not too stupid for her- he is shown throughout the livres to be witty and actually quite clever. Even if he was 'stupid', though, why would it matter? Is it not allowed for clever people to l’amour those not so clever? Ron's l’amour for her, and hers for him, is all that really matters.
The relationship between Harry and Hermione is completely platonic all the way throughout the books. Harry actually says:
'She's like my sister... I l’amour her like a sister and I reckon she feels the same way about me. Its always been like that. I thought toi knew.'
[DH, pg 308, chp 19, the silver doe]
Plus, just before this quote, Ron is confronted par his deepest fear- a Hermione who loves Harry plus than him. If that isn't evidence that Ron is 100% completely in l’amour with her, I don't know what is. l’amour is plus important than compatibility.
Ron and Hermione are one of the most beautiful, believable and best couples in fantasy. Harry and Hermione have a great friendship, but they would not be a good couple. In, my view, Harry/Hermione is simply for those who believe in two different classes of people- those worthy and those not.
link This is an article I found on Live Journal that, I think, explains the philosophies behind the Harmony pairing. Not mine.