Rabbits are going to be T1 (and not a very difficult T1 deck to beat)for very long, being until HA07, and then the entire metagame is going to change. DCK is going to be more versatile, and WU Rabbit is going to be stopped by DCK if that's seriously your main concern (DWs are going to be the top deck until HA07). DCK is going to stop all the Tele-Decks running around, WUs, and pretty much everything. It doesn't matter if he's going to be maindecked a a lot of people next format because he's still going to be good. It's going to be a slower format, and with more TKR running around, he's going to get over that. Honestly, inherit summon negation isn't as good as monster effect negation + destruction when there are a lot of cards that are summoned through effects. CED is better than D. Prison because of Xyz monsters, as well as clearing cads like TKR and DCK off of the field so you can make moves. WU Rabbit is going to be a little problem (if even that). Verz Thunderbird is twice as good, being a level 4 DARK monster, and having the same effect +300 attack (so 1950 beater), and that's still something skilled players can get over.
EDIT: CED is also extremely more versatile, giving you opportunities to do enough damage to win games, get rid of set Ryko or Snowman Eater, get rid of Maestroke, Utopia, Zenmaines, Gachi, Tiras, Adreus, Acid Golem, on rare occasions BLS and Sorc. if you've been manipulating their graveyard directly or indirectly, monsters summoned by Rescue Rabbit (prevents the Xyz summon), and prevents important ignition effect monsters like Leviair. It also saves your non-Xyz and Synchro monsters from things like BTH, D. Prison, Torrential, ect, which can be good in cases of emergency, or if you want to keep something like TKR or DCK if you want to maintain a more controlling advantage.