Dining area of JAL Sakura Lounge tend to get very busy, when get very busy there are attendants assisting waiting line and directing to open tables. It is free food, and not bad one after all, what can we say? Recent renovation of Sakura Lounge added extra dining are to less the crowding. Down stair non-dining area of the lounge do get busy at time but I think it is alright, down stair area of Sakura Lounge is never bad as up stair dining area of Sakura Lounge. It is the hub for JAL after all.
When AA had daily non-stop flights from NRT to JFK, ORD, DFW, and LAX (before SJC) NRT AC did often get busy after 4 p.m., remember had to walk around a lounge little to find a seat. Now the daily non-stop from NRT is down to two (DFW and LAX) and ORD is down to x3 weekly and will be gone next year, I see NRT AC at late afternoon not as busy as used to be. Also, I think there are people heading to JAL Sakura Lounge for free food.
If AA will entertain an idea of AC at HND then they should give a serious thought about the amenities. CX HND lounge.is day and night compare with CX NRT lounge. Because of offering at JAL First Class Lounge and Sakura Lounge, if CX decided to make HND lounge as same level as NRT lounge then likely many choose to go to JAL Lounge instead CX lounge. When CX decided to open their own lounge at HND, they knew that they had to up the game compare with CX NRT lounge or else passenger will tend to migrate to JAL lounges. I think same will be the case for AA.