Now, the Tower is not "larger" than the Warp. But it is more "complex" in its size and scale. Every dimension (A.K.A. "floor") of the Tower contains its own multiverse, in which the entirety of every floor below that multiverse is contained within its atoms. This means there are entire multiverses contained within grains of sand, with those sand-grains existing in universes which are part of infinitely-large multiverses which are
also contained within the mere atoms of the floor above, and so on and so forth, going on forever.
As far as the balcony goes, I've been using some terminology that's specific to The Dark Tower, so let me elaborate.
A "balcony" on the Dark Tower is explained as being (effectively) a place which is attached to the Tower, but exists outside of it. When someone creates a "balcony", they are creating a reality outside of reality, as shown/explained when one of the characters is revealed to be capable of creating one himself. In the
anticlimax of The Dark Tower, the avatar of the Crimson King is shown as being trapped on a balcony on the side of the Tower (the physical one), but the actuality of it is that he's stuck in a place just barely outside of the confines of reality, able to do things like toss objects off said balcony, but unable to actually leave. It should be noted that the Crimson King's avatar is so powerful that a character required an amp from
the Rose (the other linchpin of existence) in order to even affect him, yet when Roland and Patrick finally arrived to the Tower and found CK's avatar trapped, the latter had no powers, or even any real means of fighting them outside of a few pieces of the Old Ones' lost technology. The implications are that all of his power was simply stripped from him.
Granted, the Crimson King's avatar definitely had a body that was limited by a physical component of some sort (he's stated to have outright choked himself with a sharpened spoon at some point in the story), so I don't know how limited an "indeterminate mass of warp energy" would be if it were trapped in a location that was attached to the multiverse, yet outside of it.