The latter's attacking sense is way more developed than Marchisio's. Way more. He's proven that at the last Euros and the WC. So, more so leaps and bounds, rather than steps.
Marchisio is quite a good all-around player, but at the moment, he doesn't particularly stand out in any one facet. I think, although many (here) overrate him, they acknowledge this by praising him mainly for 'consistency', and not much beyond this. Currently he's a poor man's De Rossi.