Did you try to figure out Shibuya when it was under construction? ;)
Also trust me, it is great you had no issues (engineer likely since you are on HN) and were able to see the patterns, however most foreigners are like deer in headlights.
Also exits are simple. Figure out where you want to be and on their website it will say what station and what exit. Their is alway a map when you get off a platform with the exits labeled.
I was there in May and did end up going in a circle the first time at Shibuya and finding myself back at the viewing area overlooking the crossing after just following the ramps. The stairs down were quite easy to miss.
Once you know to keep walking the platform to the exit you need it's very easy for most stations.
Where I struggled was finding a specific shop or eatery I had previously visited at Ueno. Too many separate concourses and shopping areas.
Also trust me, it is great you had no issues (engineer likely since you are on HN) and were able to see the patterns, however most foreigners are like deer in headlights.
Also exits are simple. Figure out where you want to be and on their website it will say what station and what exit. Their is alway a map when you get off a platform with the exits labeled.