Going with the yellow flower theme, Mount Edna Broom, Genista Aetnensis is a lovely graceful small tree/shrub. Although quite slow growing, it's the sort of tree that would frame a front garden. Although there is no autumn colour, the flowers in early summer with its scent makes up for it.
I was just about to suggest that one @Borderline ... a truly beautiful tree, glorious when covered with highly scented golden yellow blooms and elegantly shaped branches, and with light foliage so not casting heavy shade. It isn’t planted that often as it needs space to be seen at its best, so it’s unusual and always turns heads. 😎
My pick would be similar to edhelkas, either a Liquidamber Worplesdon or Liriodendron Tulipifera - there is a simply stunning Liriodendron planted in a children’s playground, of all places, in the next village to me. It’s a real show-stopper, has had it’s leader pruned at some point and so branches out beautifully and kind of drapes. The green/yellow flowers are exotic and amazing. Great autumn colour too.
Mountainous Northern Catalunya, Spain. Hot summers, cold winters.
Posts
https://www.architecturalplants.com/product/genista-aetnensis/
https://www.bethchatto.co.uk/e-h/genista/genista-aetnensis.htm
Gardening in Central Norfolk on improved gritty moraine over chalk ... free-draining.