We were there last July spending a day each at
Disneyland and at Disneysea. The latter was awesome, fantastic theming, great classic rides and amazing ones unique to that park.
We thought the tickets were good value, we bought them online in advance and had to say which date and which park for each visit. The two day pass for two people was about £180 at that time.
We stayed at the Keio Plaza Hotel in Shinjuku which was a great base for exploring the rest of Tokyo. Their free shuttle to the parks took about half an hour. Again, it had to be prebooked and there was a choice of three out and three back to each park. It sounds very regimented but worked well. Having made good use of the hotel breakfast (!) we only needed one main meal at the parks and we thought the cost was reasonable.
We had a great time.
ford family