I agree, but the point is to not include Padme, because to preserve the suprise of ESB, the two character must be believed to be seperate. Anakin is not Vader and Vader is not Anakin, until of course, it is revealed to us later on. The reason I have him say Obi-Wan Kenobi, is for two reasons. 1)There is source material and 2) because it is a formal reference, not "Where is Obi-Wan". Much like Maul's goal is to kill the Jedi, to reveal themselves and have their revenge, this new apprentice, Lord Vader is hear to wipe out the remaining Jedi. As Obi-Wan said, Vader helped the Emperor hunt down and kill the Jedi.

That dialogue is far from the finished idea, it's just a 'predraft' of what I would do to get you seeing what I am thinking. All previous Vader references are removed and replaced with 'Skywalker' or 'young 'Skywalker'.

"My New Apprentice, Lord Vader can you hear me. "
"Yes, my master. Where is Obi-Wan Kenobi?"
"You have done well, Lord Vader."
"I can sense his presence"
"Patience. In time he will seek you out.."
"What is thy bidding, my Master?"
"Rise!"

Then have Vader bust off of the table, but instead of showing him reaching up and screaming as the final shot, just cut to Palps face smiling and laughing.

There, is that better? All of that dialogue is in the following films.