Would it be better if the the Yankees and Mets switch from the AL and the NL?

No. If they switched, the rivalry would be gone. The Yankees-Sox and Phillies-Mets rivalry is a division rivalry- that's the reason it began in the first place. If they were to switch, the Yankees and Phillies would probably become rivals, and so would the Mets and Red Sox, provided the Mets are competitive and healthy.

Derek Jeter said, after Brett Boone's homer in game 7 in 2003 that this series was as exciting as any could get unless one of those two teams switches leagues.

That said, if that happened, the rivalries wouldn't be the same. Inter-league rivalries aren't as strong as intra-league rivalries simply because you don't play teams from the other league that often and the games don't count as much in the standings (games against division rivals count double, because if you win, they also lose, so the standings change a full game, not just half a game.) The Yankees and the Mets don't have too big a rivalry and they are in the same city, but they only play 6 games a year and have only done so since the start of inter-league play, meeting up when it counted most only once, compared to the 3 ALCS featuring the Yanks and Sox.

There would be no more rivalry and Yankees can't have their pitchers hit. That's how alot of pitcher's in the NL get hurt.

The Mets can't even win the NL East, they'd get slaughtered in the AL.

Ridiculous idea. Leave things well enough alone.

The Yankees-Red Sox rivalry is far too special to let this dumb idea come to fruition.

if the yankees went to the NL they would annialate i mean they would freaking own... and if the mets came to the AL they would just get worse....

No, it wouldn't be better.