Optimal Feed for Attracting and Nourishing Garden Visitors

If you're in it for the long term, you should plant and grow natural foods for the creatures that are native to your area, especially insects, as that will bring "natural" birds into your garden, providing a wider biodiversity and a more sustainable future.
Short term, I've found sunflower hearts to be the most eaten, and suet nuggets (peckish make them I think) attract others. A source of clean water is of paramount importance.

Definitely Pyracantha & Rowan for the berries and Buddleia and Red Valerian for butterflies and hummingbird hawkmoths plus any single open Dahlia blooms & sunflowers & teuchrium (wall germander) for bumble & honey bees ... there are so many plants for pollinators & beneficial insects, just ask google for some lists!

I have a good variety of garden birds. They get premium bird seed, peanuts, sunflower hearts, Niger seed, suet pieces. All gets eaten, although some on here will feed similar or only some of these foods depending on what their visitors like. Start with only a few types and small quantities until you see who you get to visit and what they like. Clean feeders regularly and have plenty water available, for bathing and drinking, any type of dish, basin, bowl, and also them clean regularly. Put your feeders near to bushes or trees, where the birds can go back and forth, for cover and to eat. You could plant the suggested flowers and shrubs and in time have natural food sources. Good luck