Jonathan's 4yo Thomas the Tank Engine Cake

Thanks to Debbie Brown, this Thomas the Tank Engine cake was by far the most difficult and time consuming cake I have done so far. I am not critizing Debbie at all, her books are by far some of the best avaiable. It is more a comment for myself to take on such a big project whilst still an amateur. In the end it took way too much time for my liking and hope not needing to do another Thomas anytime soon.
The cake itself was a chocolate sponge, which was my bad move. I should have used a heavy cake like fruit or mud cake. Then I filled and coated with white chocolate ganache. As it was a biggish cake I made extra ganache which was fine but found it took so long to set I should had made it the night before and not the day of the build.
As I used sponge the cake had difficulty holding its shape and soon my Thomas was becoming funny looking.
At the end I finished it without the wheels, By that time I was tired and just had enough of spending any more time on it.
I presented it to the party and thankfully it was a hit.
I served the cake with a choc chip cupcake as my secondary backup if there was not enough cake for everyone.
I think as a comment for future cake desgin publishers to include an estimate time required to build a cake for novice or intermediate cake decorators so it helps guage and manage our time.
Only a thought, doubt anything will come of it.