Having the twins born on Dagobah makes sense on many levels.
The "something familiar" line could be just a vague connection with something through the Force but the Force is everywhere, it would add a bit of story reasonance if there was a bit more to it. Sometimes pointing to something in another part of the story can be very rewarding (when it isn't done in a hamfisted way like "You'll be the death of me").
It gets Yoda onto Dagobah without having to add yet another landing sequence and a ship to cover up.
It gets rid of the landing sequence on Polis Massa which adds nothing to the plot.
It makes the end sequence more simple by cutting away all that un-needed fat and enriches the basic story.