I think the dislike of G'raha is warranted.
Firstly, we're talking about a character who looks like this:

Secondly, based on the direction of his story:
I think the writing around him is of very poor quality. Not only does he have many different special powers, they're all given to him through needlessly convoluted scenarios - including time travel.
Furthermore, there's no actual stakes involved. He plays a part in eliminating not one but two of the Unsundered and at no point does he himself have to pay any lasting, realistic consequences. Being unable to return to the First doesn't count - because he wanted nothing more than to travel with the Warrior of Darkness.
We also have no option to turn him down. I don't care about his one sided friendship. I want him gone - and I'd reluctantly tolerate him if we could shoot him down. In an already bloated cast of characters, there's any number of characters we have spent time with over the years. Why does G'raha, of all characters, have to fulfil the role of 'best bud'?
The wiggly ears and widened eyes each time he sees a 'hero' grows grating, too. I'm not fond of hero worship in general, especially since the game likes to state that everything is a matter of perspective - so there's little point in glorifying those who only secure victory due to never having to face the same level of destruction as the antagonists and due to having all manner of plot conveniences to ensure that they're never at any risk of having to go 'too far' in their quest for survival.