Sparrows scared off Blue Tits and Robins

Hello, I have just joined this forum as I am new to birdwatching.

We have been feeding the birds in our garden for the last few months. It started when we had a regular Robin coming to visit us and watching us dig up the ground, so we put up a feeder in the tree and we were regularly getting Robins and Blue Tits. We enjoyed this so much we bought some more feeders for the tree and started attracting lots of Blackbirds, Rooks and Pigeons. We bought different feeders specifically for small birds and this worked but now they have been taken over by Sparrows. We looked at ways to attract the Blue Tits and Robins back as they seem to have been scared off, so we bought lots of mealworms. All of the mealworms have gone overnight, I assume early this morning and I haven’t seen any other bird except sparrows. The tree with the feeders is in between two big bushes and I can see that the sparrows are obviously feeding some babies as they constantly fly in and out of the bushes and our roof, there must be about 30 of them. I don’t have anything against sparrows, obviously, but they are not as pretty as the other birds. Is there anything I can do to bring back the Blue Tits and Robins? Also, they are eating everything very quickly the fat balls seeds and mealworms is this ok? Thank you!