Please help - what dwarf tree/large shrub to plant in raised bed

I'm redesigning a courtyard and have a circular bed in the middle, about 2.5m wide. The bed is sitting on a hardcore base and so only soil available to plant is from raised bed. I'm wanting to plant something that makes a statement but don't know much about plants as am just starting out on gardening front! It is a sunny position that is sheltered.

Any suggestions or advice greatly received!

Thanks.

Thanks very much Margot for the advice. We used to have a fig tree in that courtyard so it may be a good idea to put one back!