There's a series of units with what I believe to be gun/blaster based attacks, with one underwhelming damage skill and one support skill I don't recall being particularly useful. Felt like they were under-statted overall, though having a CD-based damage skill with more oomph might also help.
But to your point the units with only 2 skills generally feel worse than the units with 3 or 4, at least this early in.