I know this problem very well because I hunt worldwide for over 40 years. Luckily I only have so-called Euro mounts because I never wanted that the mummies of my victims look at me all the time. Nevertheless, I have no place on the walls for a long time and there are among other things buffalo trophies as well as elephant tusks lying around in many corners. It's a problem when you know that you might not live that long and you don't know what will happen to the trophies. As a young hunter, I never thought of such things. At the moment I am trying to reduce the number of my rifles a little, but also the trophy supply. It's not easy, but at times I can give as present a deer antler and sometime a buffalo trophy, the latter are amazingly very desirable by people who have nothing to do with hunting.
You will inevitably run into the same problems, but don't ask yourself such questions now. Enjoy hunting worldwide, the memories of it and the nice trophies on the wall,... as long as there is still room for them.