Location-wise it is right next to the Niigata Station. Use the Bandai Square exit. The station is under construction till 2025 so it may look slightly messy but should not cause much trouble. The side street of the hotel has plenty of good local food options.
The hotel has a hard 3 pm check-in rule, no matter if the rooms are ready. So at 3 pm there will be a line of people getting their room keys. In case you arrive earlier than 3 pm, you can sit in the lobby or let front desk keep your luggage. The more common experience is that if your room is ready, usually hotels will let you check-in a couple of hours early and if the room is not ready then you'll just have to wait. I don't understand the hard 3 pm rule at all.