Look at most of the work the SNL guys pumped out after they put the coke spoons down. It's terrible....
I never saw Trouble, but I did see BB2, and it sucked. Would it have been better with Belushi? Probably not. I think he'd kicked the bucket by then, and Goodman is a poor replacement. I like him in his own parts, but being shoe-horned into BB2 was a rotten part for him.
To my bests recollection of those days, most of the movies from ex-SNL actors bombed because they decided to take themselves too seriously on the big-screen. Comparable to the Jerry Lewis transformation of the 50's and 60's. It could be because they could not transition from skit comedy?