Navy/brown/green/dark red (wine?). Knits would look nice with that, IMO.
Also best not to mix up the A's and C's in my experience.
Umbrella, I think the problem is the black knitted tie. With a white shirt and grey suit it would be awesome, but it somehow sucks the life out of the rest of your clothes here. I think that. more than the shirt, is where a little warmth is missing. I'm not sure knitted is the way to go here - a finer texture would integrate better - but if the knit it must be, then it needs some colour - maybe some kind of burgundy or restrained rusty shade. But it's the black that's not flying here, I'm sure of it.
(And if it's not actually black, I will just shut up...but it looks it in the pic)