Sometimes birds will 'desert' a particular area for no apparent reason, no matter how many goodies you put out for them. About three years ago the house sparrows (a species which you probably know has been going through a rocky time lately, the RSPB has it on a watch list) disappeared entirely from our area. We went for several walks around the area, binoculars at the ready, but not a single sparrow to be seen. My wife was so concerned, she wrote to the RSPB. But later in the year they came back. And this year they're in plentiful numbers. You just can't answer for the birds.
Have plenty of shrubs in the garden for birds to perch on, but keep them trimmed back and twiggy, not too many big branches that cats can climb.
We've just put up a new nestbox on our birch tree (28mm size - for blue-tits) seeing as the old one had got decrepit* and the hole had become too big for the blue-tits' fancy. My wife reports they're already taking an interest in the new one. Fingers crossed!
*BTW, you're supposed to take the box down and clean it out every autumn, anyway.