Yeah, there's a general consensus here...Chaos Castle's ending just ruins it completely. It can nullify everything you've done up to that point, and the fact it's right at the end means if you drop stars there, chances are you're done for. If only it was just like 10-15 ministars a hit instead of half.
Seriously, I hate how many "half your ministars" situations are in this game. It's ridiculous...
The storm cloud section of Airship Central is almost as bad, however that's halfway into the board, meaning you can recover, and it's always a 33% chance of having it happen, rather than say that chance possibly jumping to 50% or even 67% on Chaos Castle, and special dice blocks are much more likely to grant you one-turn immunities there. The rest of that board is quite nice too.