Another branch will become leader; For a tree that young it will look fine in a year, Bigger conifers will also develop a new leader but it will take a few years of growth to develop a regular appearance. Sometimes a mature tree will always have an oddly shaped top.
Assuming you mean Prunus laurocerasus and not Prunus rotundifolia, height and spread will be 4-8 metres tall with a spread of 8 metres
wide. That means, from the shapes you see in your diagram, it will
look most like the 'spreading' one eventually. If you plant more than one, they will need to be a minimum of 8 metres apart so they look like individual large ...
Here are a few suggestions, all from this page.
Banana Shrub, Michelia figo: fragrant, banana-scented flowers. Heaviest blooming in spring, but blooms all season.
Night Blooming Jessamine, Cestrum nocturnum: small, not very showy, fragrant flowers at night during the summer
Arabian Jasmine, Jasminum sambac: fragrant flowers from summer into fall, or year ...