Open, hassle-free Hikari recommendations

Hello

Sorry, yet another ISP post.

I'm moving to Den-en-chofu (Ota, Tokyo) soon and looking at different Hikari providers. The mansion supports it, but trying to find one that matches my requirements (if any even exists).

I'm fairly knowledgeable when it comes to home networking.

Speed and price would be nice to have as high and low of course, but more importantly:

1. Want to be able to use my own router. I understand that most providerd provide their own, but I would prefer to use my own so I can configure it as I want.
2. Open, public IP – don't know how it works here, but back home some providers put you behind NATs which screwed with the routing, making gaming really iffy. Public IP, no routing issues. A good connection for PC and console gaming is a must.
3. Unlimited traffic, no throttling – No cap to our monthly usage, or throttling by the ISP
4. Preferable – if possible no or short contract length. Don't want to be tied to it for x number of years in case circumstances changes.

Any ISP you know of that hits most of these marks? Or that Japan providers handles in a different way so I don't need to worry? Or something else I need to keep in mind?

My agency setting up ライフライン for me is suggesting Softbank, what's your take on it given the above?

Thanks!