The variety of wedding cakes is immense - from traditional and ornate to modern and simple - the choice will largely be determined by the type of ceremony you have. You might want to consider a separate tier of the cake for the older guests who may have dietary restrictions - they need to equally partake of your reception. In any case, the caterer or the baker of choice can give their best advice once the number of guests, favored taste and style are known.
A lasting tradition has been for the bride and groom to save the top of the bridal cake, to be reminisced over glasses of champagne on your first wedding anniversary. Transporting this memento needs to be considered if you wish to continue this tradition.
