Nobly; Tomic looked very mature, consistent, intelligent, big serve, mixes up all his shots, but a questionable net game. He looks bigger and stronger now too. But to be honest, there are many other players I did not get to see. Tomic and Harrison but Janowicz has a serious weapon with that serve. Berankis is a nice player too.
Janowicz indeed has a big serve, which is a major asset on this surface. He is, however, extremely unpredictable and his backhand is substandard. I also don't quite agree with your assessment of his movement - I find him gangly and rather awkward - but he might have improved.
But he finds himself in quite an easy section in which any player could make it through (besides Janowicz it's Haider-Maurer, Cipolla, Muñoz-De la Nava).