It irks me a bit that they made SAM like this.
They recognise that MNK (and arguably the two casters) in HW was an issue- the concept of no utility/party synergy didn't work out and made it undesirable (technically also why WHM got left out, no way to properly buff the part, which means no synergy).
And now they pick the same idea that did not workout for over a year- but err on the side of excessive power this time, to the point some utility jobs can't compete (and well, BLM, which isn't that much of utility but I digress).

This is walking on a razor's edge- SAM needs a dps surplus so that it matches almost perfectly the overall utility options. This is very hard to do (and even then there would likely be disagreements- a SAM is "all the eggs in one basket"; if he dies, the SAM party suffers more than the utility-based comp. If by some chance the Astro has to dump a single target card, the SAM comp gets a slight edge. Things like that).
I just secretly hope this is a grand experiment so when 4.1 (optimistic) or 5.0 (realistic) hits, they can make this concept work ingame to everyone's contentment.