Still fixing up my Monster Manual.
The spread on pages 24 and 25--with a competently done basilisk and a really quite nicely rendered behir about to petrify and electrocute each other, respectively--illustrates the problem with both of them.
They're both big lizardy things. And since the game has dragons in it, big lizardy things risk eat into the terrifying and isolated psychological space that should belong to dragons alone.
I basically deal with this problem by making them really small.
Otherwise the basilisk is an awesome monster with a cool name, plus I've already used like 3 of them in my campaign so I can't and don't want to change them much.
That crude sharpie drawing in the lower left is a sketch of some pre-lapsarian state of mythical equipoise where the medusa, cockatrice, catoblepas and basilisk stood mutually blocked from each others' gaze by the Egg of the World, which they all looked at, waiting to kill whatever emerged. How the clinamen that resolved this stalemate was introduced I haven't figured out yet.
(And yes, taxonomy pedants, we all know behirs--being salamandery--are amphibians).