I guess the only thing that bothered me about SR and Jason was that Clark didn't come clean with Lois at the end.
But if he had, the suspense for a sequel might not be so great (for some, anyway). I think that's the single reason that Smallville has been so successful--it's like watching a soap opera. They never give you what you want, and if they do, they find a way to take it back. If LnC had drawn out the revelation and relationship longer, who knows how long the series might have lasted? That's always been my thought anyway.
I think the things that bother us the most are often ploys to keep us coming back for more.