Project 1999 - Officials: Plane carrying Brazilian soccer team to Colombia crashes, 76 dead

Can they design these crafts to sustain flight during complete engine failure or would that require a completely different lightweight chassis?

These crafts aren't 757s, they're much smaller...

I know speed is a problem. Surely they could design a wingspan and hybrid chassis that's designed to glide into a crash landing. Alternatively, let people take their chances parachuting out (survivors mean descent was slowed and controlled to a degree, basically an intentional crash landing) which means speed was low enough to risk parachutes (high speed with low altitude obviously wouldn't work)

I guess even if they could crash land better, it'd be a win and that's basically what gliding is.