Finally worked out how to stop squirrels and magpies getting at food whilst stopping finches and sparrows wasting all the food

So I have a really bad problem with squirrels, magpies and pigeons, which scoff every last bit of food if they can get their mitts on them. So I bought super expensive hanging squirrel proof / big bird proof feeders. These were great, up until the point that we got a huge mob of greenfinches last summer (around a hundred). The finches would sit on the feeder, all comfortable, scoffing around a kilo of sunflower seeds in a day (had two of the weighted squirrel proof feeders with 8 ports in all). Not a problem I thought, they're eating them, that's fine. Then I found out that they were chucking about a third on the ground and nothing was keeping up with eating the waste (not even the pigeons which we then had huge numbers of) so I stopped putting sunflower seeds out in the hanging feeders and only put them on the table (the weighted squirrel proof ones don't have a tray to collect, plus they throw out so much that the tray wouldn't be able to keep up). So then this winter I put out fat balls for the birds, inside a squirrel cage. And found that they were going down really really fast. I then saw the magpies having a go at them and taking off with huge chunks. So after much testing and trials and tribulations I think I've now got a squirrel/magpie/big bird proof no waste from sparrows/finches solution. No hanging feeders, the finches have dissapeared, but got house sparrows now, which seem to be even more wasteful than the finches. Put mealworms out in the hanging feeders and for every worm that goes in their mouth about 5 go on the ground, we've got dunnocks but they simply can't keep up, and I don't want to encourage rats. Now we only have standing or hanging bird tables, covered with squirrel cages, with chicken wire round the bottom layers. This allows the wee birds to pop in through the upper layers of the cages, but stops the squirrels, magpies and pigeons. The fact that they're flat feeders means the robins can eat there too, and stops the sparrows/finches from wasting stuff as they drop it back on the table. The wee birds can be quite cautious about going into the cages, but I've found that putting perches on the outside can help to encourage them in, so that they can have a wee sit outside first before they decide whether it's safe to go in. Just thought might be helpful for anyone who is struggling with magpies/squirrels and wasteful birds which drop all the food from hanging feeders :)