Overrun with Starlings!

I started feeding local garden birds a couple of weeks ago and got such a kick out of seeing all the birds come and eat my homemade bird feed recipe but I didn’t anticipate the colossal flock of starlings haha! There’s been that many, I fear they’re going to become a nuisance to my neighbours - of which I have an abundance of, too! I love watching them but the mess they make on the surrounding garden fences of neighbours and on our decking, garden furniture and fence panels is getting a little much to be honest. I don’t want to stop feeding them but I do want less of them visiting. The other birds I’ve seen visit, jackdaws, crows, blue tits and great tits can hardly get a look in lol. Any advice on how to reduce the amount in my garden? I had about 30 the other day!