What style of coat to wear with dresses? Help!

[Fudgeytastic]

I'm mid 40's, size 18, big boobs and bum and have found a style of dress that flatters my shape. Knee length and flares out a little. My question is, what type of coat do I wear with dresses? I commute to the office on public transport and have to do a fair bit of walking so it needs to be fairly sensible. I just don't know where to start as I used to be a jeans and weatherproof jacket sort of woman

I wear a wool riding coat for my commute unless it's absolutely torrential rain which is surprisingly rare on a London commute. I carry a small umbrella in my backpack in case of sub-torrential rain.

Eg this
https://www.johnlewis.com/hobbs-caitlin-wool-blend-riding-coat-wine/p109440234?size=12&s_ppc=2dx_mixed_fashion_BAU&tmad=c&tmcampid=2&gclid=Cj0KCQjwmvSoBhDOARIsAK6aV7hed8IFzmB_duwqJ1hD9_TRqcyXOJ2MDPSvc_mmfXGNEC0-BYRNi0AaAnupEALw_wcB&gclsrc=aw.ds

I’ve never got on with macs so I tended to go for hiking jacket on super wet days. I bought a shower proof Polarino 3/4 hooded hybrid that’s plain black, soft shell and slightly fleecy on the inside that is ok if work and waterproof needed. I have a smart wool coat for dressy days, a quilted and hooded long coat that’s mid smart and a couple of style over substance short padded/quilted things. Oh and there’s the amazing orange check coat I bought in New York 15 years ago for very swanky autumnal days.

With dresses length can be an issue. Nothing looks weirder than a mini under a short 3/4 coat as that length of coat is designed for skirts to show below it and no one wants the forgotten your trousers look.