I agree, it could have been included. I wouldn't have had a problem with it. And I certainly wish Qui-Gon was in it, as he is my favorite Jedi. However, I can see why it was left out, as you want the audiences emotions to still be jarred from the ending of the battle, the raw emotion of the child birth, the stun of Vader's birth, and the Twins' being split. You kinda want to overload the audience at the end as quickly as possible.
I mean, ANH ends this way, ESB ends this way, with just a quick ending after the climax.
But yes, I would have liked the Qui-Gon and Dagobah scenes left in, but as I've held all along, I see far superior Special Editions of these three films being released at some point. A CGI Yoda, reinserted deleted scenes and a few CGI things touched up to make the films 'archival' as he likes to put it.