Similar situation here, I bought a GT JTD a month ago, like it very much but some of the posts here are a bit worrying!
At the moment my thinking is - my car is great, there are some niggles, this forum is brilliant at telling me which are normal and which need attention, and some of the niggles turn out to be 'working as designed', just not as I expected, but that's no surprise if it's your first car from any brand.
On the 'big one' - the JTD waterpump/cambelt problem - the first thread in the forum contains good advice. My car like yours is 2005 and on 37000 miles. Now I paid a highish dealer price and got a year's warranty so I am not too worried, but when it reaches 5 years old late in the year then I will have the big service with the cambelt and waterpump change. If I was not on a warranty I think I would bring the belt change forward. Suggest you consider what warranty you have if any and how much risk to take. The Alfa change interval is 72000 miles (you're nowhere near it of course) or 5 years, which you are close to, and TBH both thresholds need to be taken note of, from others' experience. If your car is 5 years old now and you bought from a dealer then the belt should have been done already and if not you have an argument for getting them to do it as the service manual does specify it.