"I got interested in philosophy because I had broad academic interests in lots of topics ... physics ... economics ... metaphysics ... ethics ... so when I eventually found philosophy that seemed like it, the core field with connections to all the other fields ... getting a better and more detailed understanding of that big picture of philosophy as a whole, and its relation to other fields, was the most interesting part of studying philosophy."
So you've approached philosophy with the same intellectual rigor that you'd use to approach any other academic discipline, and have sought to find in philosophy a "big picture" which integrates it with other disciplines, if I understand you correctly. Perhaps that's commendable, and it's certainly how philosophy's been approached since way back when.
But you also said you're not finding philosophy much fun any more, and actually I'm not surprised. Your approach seems to treat it just as another academic discipline (correct me if I err). Academia can easily rob us of spontaneity, freshness, and fun. Consider a scientist whose whole world exists under a microscope. When he finally makes it out of his lab each day, he fails to notice the simple beauty of nature around him - the warm sunshine, the flowers - because he's so caught up in his intellectual deliberations.
Most people never see the sun, not really. They see a radiant disc in the sky and label it, dismissively, as "the sun". They don't really
see it. Not with the freshness and wonder of a young child, anyway.
" ... what is it that constitutes your interest in philosophy, such that you seek out a forum on the topic?"
My interest in philosophy is directly connected with awe and wonder. Awe and wonder at the miracle of my own being, the miracle of consciousness. It's rapt meditation around that most fundamental of questions: "Who am I?", without any attendant need to intellectualise that question. It's the realisation that intellectual pursuits ultimately get me nowhere, when it comes to that deeper journey into the nature of Self.
It's the realisation that "of making many books there is no end, and much study is wearisome to the flesh." (Ecclesiastes 12:12). It's the realisation, when I move beyond intellectual positioning, of "the peace that passes understanding" (Philippians 4:7). (I hold no particular religious convictions, but find much wisdom in scripture.) It's the contemplation of that still, quiet centre which is the essence of my being.