for me, the danger with tweeds, flannels and knitwear is straying into 'dowdy' rather than 'stylish' territory.
I think I have been 'guilty' of looking dowdy at times, especially as I am in my mid twenties.
But do you see a difference between "looking dowdy" and having a subdued rather than a flamboyant taste?I personally don't mind the "dowdy" look that much... it's only really bad when resulting from uninspiring 1970-90's Tweeds (olive... blech!) and modern shirts and trousers.