Used car with driving fun and everyday fitness for approx. 16k

Hello dear Motor-Talk municipality, I would be happy about a few suggestions regarding a new used one. My budget is at 16,000€, the whole I could stretch to a maximum of 20,000€, whereby I would prefer a car around 16 or less, so that I still have reserves if surprisingly a repair or similar is pending. Some information about me: I usually only drive short distance (2-10km) and 2-3 times a month long distance (300+km) otherwise the car should also allow me My first car was an Alfa Romeo 155 2.0l twin park. It was replaced with my current car BMW Z3 2.8l roadster. Both cars have given me a lot of pleasure, but the reliability of the Alfa left a lot to be desired and in the meantime, the lack of space in the trunk and the fact that it was only a few minutes away from the car was annoying to me at the Z3 and the fact that the car had a lot of fun. In addition, I think the Z3 is much too exhausting for longer rides and often completely useless in winter, because the roads are only partly cleared in winter, so I can not move the Z3 at all, because it is too deep. I am already spoiled by the 2.8l in-line six cylinder in the Z3, meanwhile the performance is too low, however I never had problems with the engine, it runs like a 1 without much care and In the next 3 months I want to get a new used car. I don’t want a convertible anymore. It should be a station wagon, a limousine or a coupé. The car should definitely be better than my current and in addition to half way comfort also offer driving fun. In addition, I want more usability, i.e. more space in the trunk and the possibility to transport at least 4 people. I would have preferred to have an older Alfa (à la Alfa Romeo 75 3.0l or even 1.8l Turbo or an Alfa GTV6) again. But I didn’t want to do this dream for the time being, because I want a certain degree of reliability and I shouldn’t get rid of the car even in winter. I’ve already informed myself a little bit about two dream cars, the BMW 335i and the Audi S4. Both cars I find absolutely great; insurance, consumption and tax would be perfectly fine. However, any repair costs will scare me off very much. At the 335i unfortunately only the N54 engine is in my budget and about which I have read too many horror stories (maybe I have also overly scared because I have stumbled too much in forums). Since the S4 for me only the 3.0 TFSI engine comes into question, and this is only installed since 2009, there is very few cars I could afford and I am afraid of them, because I would not like to take advantage of the cheapest offer only to have to put X-thousands € in retrospect. Again: -Budget 16,000€ (absolute pain limit 20,000€) -Kombi, Coupé or Limousine -More space and comfort than the Z3 (should probably not be a big problem -More performance than the Z3 with its 193hp offers – petrol or diesel is basically no matter, whereby I tend to become a gasoline tanker I don’t care about automatics or manuals, but as long as it’s not a very old, slow automatic, I would be happy with automatics. Please let me know if I have forgotten important information or if you need any other information. What can you recommend to me? MfG Jim