Beria was a monster in his personal habits, but being NKVD chairman means having a perspective of the Soviet State that very few people actually have. Sure, you're drilling teeth out of dissidents and working wreckers and sloths in the gulags, but you're also listening to what they're saying before they get the third degree.
The man who took over Nikolai Yezhov's job would have to distance himself from the policies of Stalinist Terror and the nightmare he had created, or he'd be feared as being a Stalin in his own right. I'm not sure how much Beria wanted to reform, versus how much he HAD to reform or wind up getting beaten and killed by his new replacement.
Irregardless of his motives, Beria would prefer to get Western Aid for rebuilding the Soviet Union and probably being able to deliver somewhat on his pledge of improving the life of the average Soviet citizen. There would be a palpable fear of Stalin's headsman from the rest of the Politburo, and I see Beria's reign as short and subject to at best his removal, if not his execution.
This could do a lot of good, at least in terms of Beria having to appoint reformers and idealists to office, and probably leave the Soviet Union in better shape after his removal instead of Khrushchev. The Soviet Union would probably not be in a confrontational posture with the United States--an earlier dentente with the west. No Cuban Missile Crisis, No Berlin Wall, but perhaps an earlier oil for grain trade with the United States. Whether these trade ties continue to grow or they wither is harder to say.