If you add a bonewall maybe add a plague or something?
Unupped Plague is woefully slow, both to cast, and for its effect to work.
Probably the only efficient way of synergizing with Bone Wall is to use some instant or repeatable damage-based creature control (Lightning, Shockwave, Rage Potion, Owl's Eye, Otyugh, that sort of thing) so that you can pick off small creatures and use them to fuel your Bone Wall. Of course, that would be a whole different deck altogether.