Well, he is already capable, he just dont/cant show it (he is like a WMD, as his CO says, and the show/novel does a very good job in portraying that, without having him to go full power at evey moment for whatever silly reason). If you recall the first episode when he blows up the fleet in the flashback, he did that at 10?
Anyway next arc (yokohama), which i supposed is the last for season, will have him basically in full powermode, and it will reveal lot of details of his power/retraints, platoon and family, but it will also spread around on the other characters (also his schoolmates will become more aware of tatsuya capabilities) . From yokohama onward is pretty much always him in full power mode engaged in something more serious than school related stuff (even tho school will always be a central part ofc), and it will deepen the story of yotsuba family (past and current), relations between the 10 master clan, and strategic class wizard.
Anime follow the novels word for word almost, so i really expect a second 24 episode season if not a third (as novel are still going and the story after yokohama is pretty long and intertwined)