Try something like Malus (Crab Apple) 'Golden Hornet' Compact,
upright, relatively trouble free. Choose a plant on a rootstock
suitable for your situation. On a semi dwarfing rootstock it won't
grow very quickly but it will flower and fruit at a young age and
won't outgrow its space. A sweet cherry on a dwarfing rootstock -
flowers fruit for you, or more likely the birds + autumn colour.
Prunus incisa 'Pendula', a little gem of a weeping tree - it will
never get very big, we've not had ours long enough to tell for sure
but it's looking like many years to exceed 10ft, an absolutely perfect
miniature for a small garden; flowering now and good autumn colour.
Conifers? Chamaecyparis lawsoniana 'Ellwood's Gold' very slow tight
neat upright form with pale yellowish green foliage, again many years
to exceed 10ft but unlikely to outgrow its space - don't be fobbed off
with other forms of C. lawsoniana without checking tho' because some
of them grow as big and as fast as Leylandii. These are all easy and
not too picky about soil.
Some Maples might suit but need careful siting - like protection from
cold winds, humus rich reliably moist but well drained slightly acid
soil - that gardeners' dream about as common as hens teeth.

Very sound advice indeed. BTW can anyone tell me why nothing seems to eat
the Golden Hornet fruit? Mine just sit there and eventually shrivel away.