Considering that Raito's big problem at the beginning of the series was being bored, I wouldn't be at all surprised if he missed the excitement of matching wits with L!

I was kind of hoping, in the first arc, that Rem clueing Misa in again would screw up whatever plan Rem thought Raito had, but apparently not. *sigh* It's a pity what happened to L, though sooner or later one of them had to win, or things would have gotten seriously repetetive.