Should we show favoritism

I've recently been working on designing and building bee houses. I had put up one cheaply made house that I'd bought several years ago. Bees did nest in it, but it fell apart not long after. I also took a log that had been laying around, drilled holes in it, and mounted it on a pole. The bees nested in this log as well. As I was looking at examples of solitary bee nests, I saw there were nests that people put wire over to keep the birds out. It got me to thinking, should we show favoritism for a certain species when it comes to helping nature? Should the bee houses be built without protection, and if the birds eat the larvae, then we have helped the birds? Or should the bees be protected, since after all it's the ultimate goal to build bee houses to increase the native bee population. There are times, in nature, that I don't agree with intervention, such as one species using another as a food source. It's sometime hard to watch (hawks with songbirds, snakes with frogs), but it is nature, and as much as I love the songbirds and frogs, the raptors and snakes also need to eat and survive. It all creates a healthy ecosystem. I've come to the conclusion that the answer lies in balance, which is so much of what nature relies on. Maybe build equal numbers of bee houses, and protect half of them. That way, both bees and birds can benefit. Check back with me next summer, and I'll let you know how my building project progressed.