I don't think your age would be a factor here even if it takes you a bit longer, but it will definitely be harder if you're not sure in the back of your mind that you really want to keep going, particularly if there are other demands on your financial resources. It comes down to whether you want to go the full deal or not, and it sounds as though you have more or less decided that the answer is no because you've achieved pretty much what you set out to do. Building and flying is already more than most people ever achieve so deciding you've done enough is perfectly OK. In the end whether to stop or keep going is something only you can decide.