I use Ome line, Chuo line, and Yamanote line to commute. So I have to change trains a few times (But some Ome line trians are directly connected to Chuo line). It takes long time to go to the university. When I have 1st period, I get up at 6:00 a.m. and leave home at 6:50 a.m.
Moreover, trains are often crowded and delayed. Two weeks ago, Chuo line was dalayed about an hour and I couldn't attend 1st period. Chuo line is always dense in morning and in evening. I think Chuo line is more croweded than Ymanote line. Since I used only Ome line and the time to commute was much shorter when I was a high school student, I didn't imagine it was very tough to go to the central part of Tokyo.