The Enterprise-D had no quantum torpodoes or pulse phasers.
As far as onscreen material is concerned, the only difference between photon torpedoes and quantum torpedoes is that the latter is bluish-white when fired. But otherwise, there's nothing to suggest that other ships--including the Galaxy-class--can't also now be stocked with quantum torpedoes (provided they can make enough of them). And pulse phasers aren't all that new--both the original Enterprise
and the Reliant
had such weapons in Star Trek II. If anything, the Defiant
was kind of old-school in that regard.
nor ablative armour or a cloak (granted, on loan from the Romulans).
Those aren't weapons, those are defensive systems, which wasn't the issue raised. As far as weapons
are concerned, the Defiant
isn't quite all that
, but they are very considerable for a ship that small.