Madeira cake alternative

[HamishBamish]

I'm making DS1's birthday cake soon and would like to try something different form the usual madeira cake I've done in the past. It's going to have to be something fairly robust, as it's going to be stacked (with dowelling), crumb coated, covered with sugar paste and decorated. There will also be a certain amount of carving involved as it's going to be a topsy turvy cake.

I would like to try and do something a bit less dense than the madeira if possible. Any tried and tested recipes out there?

How about flavouring the cake with lemon? Or using the madeira recipe but making it into a marble cake or rainbow cake - looks great when its cut and a surprise too!

By topsy turvy do you mean the layers at odd angles? If so you can get a cake tin from Lakeland that gives that shape.

Genoise sponge?