How can I help my cherry tree?

So I've moved to a new house in the past year and this cherry tree is in the garden.

It looks pretty leggy, a lot of dead twigs and it doesn't flower much in comparison to other cherry trees.
There is a big pile of leaves and grass cuttings at the bottom so could that be causing the issues?
Could it be pollarded vigorously to rejuvenate it or would that kill it?

Any advice and tips would be most welcome!

 

Eeek! First thing to do is clear away anything piled around the base of the trunk. If the bark is sound, no fungus or soft bits, the tree is worth saving. Try to get rid of the old Ivy. Wait until a dry spell in Spring or summer, then cut out all the obviously dead twigs, right back to a bigger, healthy branch. Same for any crossing or obviously damaged twigs and branches. I'd leave it at that this year, then reduce remaining branches next summer if it's too high. If the trunk is damaged, not much point in trying to save the tree.

 

I would just clear the site and start again.

I had 2 cherry trees,needed pruned,left one to recover for 10 years and it just turned into an ugly big tree. Plenty cherry blossom but ugly when the leaves dropped. One met the chainsaw last year. So much light in the garden again and that part of the lawn has been boosted.
The tree in the front will be pruned this summer again and if it still looks like a monster its getting removed.

Btw dont cut any wood until midsummer or else theres a risk of silver leaf disease.