I have done 2 castle cakes before so I'm not concerned about doing another one for next weekend. I actually really enjoy making them. Here's the problem though. I usually make a 10" round for the bottom tier and a 6"round for the top tier. That is no way near enough to feed 75. So I need opinions. Here is the serving chart I use. http://www.earlenescakes.com/ckserchart.htm

I could do a 12" round on the bottom with a 9" round on top of that but that will still only feed 67 people. I hate to go up another tier because I have to drive this thing fully assembled. I could attempt another tier though since the drive is only about 15 minutes. I just don't know. So if I do another tier it would be 12", 9", 6". Any opinions? Has anyone ever done such a big castle cake before? TIA

What about the option of sitting those 2 round tiers on top of a single layer sheet cake? You could decorate the sheet cake with a mote, grass, etal.

I used the 12,9 and 6...it's in my photos. worked pretty well. I like Indydebs suggestion too.

wouldn't the two tier's crush the sheet cake? They are pretty big tiers. I of course would use support but that just makes me nervous. I think I'm going to ask the woman what she would prefer. I think she will be ok with the 67 servings since 25 of the people are kids and both of the parents will not show up for each child. Thanks for the opinions

Or what about the old trick of a spare cake out the back to make up the extra portions if you don't want to make your castle any bigger than usual?

I did a castle cake and made cupcakes to surround the castle. They had flowers on them. I did not like the finished look but that is what mom wanted. I think a cupcake stand with a dozen or so cupcakes on it for the kids would work good and then the cake as you have planned my be an option. I personally do not find it harder to make a cuppie, small decoration on top.