While someone more knowledgeable can perhaps compare the Roman army of the late Republic and Civil War with, say, the Roman army of the Punic Wars, I just want to point out that there was no such thing as the "Marian Reform", so there's no way to compare an army immediately before it with one immediately after it. Please see, all courtesy of /u/XenophonTheAthenian:

1. There was no such thing as the Marian reforms[1][2]
2. The expansion of Roman armies were by Sulla, and not through changes in the citizen group that can be conscripted, but in the magistrates who were allowed to raise armies.
3. Roman citizens and soldiers did not become blindly obedient fanatics to their senator patrons and army generals [1][2]