Actually, the saucer likely would have fared better. It was the damage to the warp nacelle that turned a severe impact into a catastrophe. Even if the saucer could not avoid impact, it is very possible the collision could have been survivable.
Now, whether this would still have triggered a time loop is another question. If it did, would time reset for the entire Enterprise, or just the saucer section? Then would they have ended up with two saucer sections, with living crew on both? Or maybe it would recreate the stardrive, with the original still flying out in space. Argh... this is starting to hurt my brain. :-(