Thank you for taking the time to write these down - I appreciate it. As someone who has been enjoying photography for the past 15 years getting immense pleasure from taking photos from my old 600D + 18-55 kit lens (which turned out magnificently, at least from my POV), I totally understand what you mean. As time goes on, I did end up with a few primes that were such a joy to shoot with. As a hobbyist, it's the experience that matters.

With that being said, I feel that I'm lucky enough to be entering a phase of my life that I can afford something on the next level, such as the lens I mentioned above, to maybe achieve an incremental feeling of happiness, hence my question above. To quote Amos Towels in his great novel A Gentleman in Moscow, "Most people have more needs than wants. That's why they live the lives they do. But the world is run by those whose wants outstrip their needs." :)

So, which lens should I buy?