I agree that despite thematic coolness, the salvagers are in the wrong place at possibly the wrong time.
Phase Salvager easily replaces PA in an Aether/Earth stall by giving a free 2/2 body along with the innate 'PA' - if your shield is destroyed, just salvage it back for
like nothing ever happened. It doesn't help that the one of the best shields in the game is in the same element.
Graviton Salvager has no relevance to it's element and is easily outclassed by its Aether counterpart on just about everything except for being a 1-drop as opposed to a 2-drop (which doesn't really make a difference since Phase actually deals damage.)
I think Graviton Salvager should be removed/overhauled into something much more useful instead of sticking with a mechanic it just won't well with (alternatively, it could be elementshifted as will suggested). Phase could be easily fixed by making the casting costs for it more expensive (I see a 3
2 | 2
Salvage as a step in the right direction.)
The mass shard change is beginning to feel a little thoughtless and doesn't necessarily solve every problem (for example, Instosis is still Instosis, and SoSac basically just doesn't mess up a mulligan anymore.). I think it would be wise to break the thematic unity of the shards a bit and have some cost
while others cost element, depending on what fits better. (For example, SoV could probably cost
without too big of a change and SoD should just give ~20-24 Max HP consistently since it is now
only.)