Mount Nokogiriyama: how steep?

Basically I want to know how steep the hike is up to the temple.
And if there is anything to see on the trial.

Not all that steep - the path up is paved, and at some places there is a handrail, but you certainly do not need to use it. There are statues under large overhangs of the rock, a tall cut-into-the rock face of a standing Buddha, and a viewing platform at the top with a great view of Tokyo bay. Overall it is a good climb. If by car, I recommend starting at the parking lot behind the mountain from the ropeway/cable car. The cable car will take you approx. half way up if that is your preference.

https://www.google.com.au/search?q=Mount+Nokogiriyama&rlz=1C1GGGE___AU...

pictures of the paths and sights along the way

I plan to take a train from Nippori to Hamakanaya the earliest train possible. Is there a travel pass for this journey? According to Hyperdia it will take more than 2 hours, which is fine if I leave early.

How long did it take to hike up to the top?

I noticed some people mentioned taking a ferry, but the only one I saw was the one that came from Kamakura area. Is this quicker and cheaper or about the same?

I believe the ferry takes slightly more than an hour - it is several years since I last used it, so check if serious. The hike up and back down can be done in less than two hours if you don`t linger.