Which tree?

We have standard Photinias, as well as photinias as tall shrubs.
As standards they seem to be slower growing. But look attractive, which makes up for it and you can simply trim to shape very easily.
Spring flowering cherries look lovely, but make sure they are easy to manage and the upright type, like Amanagowa.
Have grown Rowans before, very nice smaller trees, I think we had Joseph Rock.
Any of these would look good as a centrepiece, and not take up room or be bulky.

There are several varieties of Cornus (dogwood) which are very attractive for most of the year. I particularly like the different Cornus Kousa or the Cornus Controversa. They grow slowly and would take about 20 years to get above 4 meters.

The Tibetan cherry is nice - lovely dark red bark that peels and looks gorgeous in the sunshine. Not too tall.

Weeping pear is elegantly shaped and reliable. It can be trimmed to shape if necessary but mine must be fifteen years old and is still less than 4 metres.

Pyrus salicifolia Pendula, is a an ornamental Weeping Pear tree. It is suitable for a small garden and will grow on any soil. Pyrus salicifolia Pendula trees can reach a height of about 6 metres at most, but can easily by kept at 3-4 metres with a little pruning.

Many thanks for the suggestions, I shall have to look up some of them. I have decided against flowering cherries as the interest is too short lived for me. I know Alan Titchmarsh often uses Amelanchier in his garden make-overs, it is my front-runner so far. Please keep the ideas coming!

ffinnochio that sounds lovely but I looked it up and apparently it grows to 26ft high and 26ft wide!!

I'm very intersted in this post because I have a strip of garden which used to be veg and would like to change it ti shrubs or spreading plants like cotoneaster, can't decide what I want exactly

How about a Transitoria?
Beautiful white blossom in the Spring.
A wide range of yellowing coloured leaves in the Autumn.
Lovely clusters of small, orange berries that can last through to Christmas, if the blackbirds don’t get them first!

It’s shape tends to grow out rather than up.

I’m sure you could prune it so that it doesn’t grow too tall.

Would also suggest a flowering cherry blossom. There are many varieties nowadays. Or an acer with foliage that changes with the seasons?
What a lovely project sal although I'm sorry about the RA.

May I suggest an Amelanchier, they have beautiful blossom in the spring, followed by fresh vibrant leaves, then red berries and flame coloured leaves in Autumn.

How about a Rowan ( keep the witches away) ?
We have an Indian bean tree in our garden. Lovely blossom and delicate twiggy branches in winter. We also have a beautiful tulip tree but they can become quite large.

How about my favourite a winter flowering cherry?