Oh, who cares? Even the shows that do go in for imaginative aliens always have someone who is just a human in an obvious costume. Yeah, we all get tired of the vagina-headed aliens of the week, but truly "alien" aliens can get just as tedious and boring. Just look at Stargate Universe, its aliens were CG and never spoke English. And it was boring.
The solution is better writing that utilizes the weakness of a budget and turns it into a strength, not gimmicky attempts at creating a realistic alien.