There is. Some are with or without a roof and others are for people with disabilities.

Vegan not really, vegetarian a little chance

Yes, I have lunch.

There is no Hanami plan. It is not close enough to be able to see Hanami from Denny's! You can not see the cherry blossoms in Shinjuku Central Park unless you enter the park! Therefore, I do not think that it will necessarily be special to the season of Hanami ...?