Love the black/charcoal look as accent colour (with brown undertone to complement bricks). if you could sand back some of the wood and stain it, maybe paint some of it black/charcoal to break it up would look amazing. If the wood does not stand up to sanding (no grain or not made for raw wood look) then you could add some panels to break it up/add texture not too much black - weathertex is a material I've used recently and can highly recommend.

1. I'd probably start with removing the ornate lines on the gables. It seems a bit 'busy' and dated with the brick and gutters. 2. I'd also paint/replace the gutters to match the roof colour or even the garage door colour. Gutters aren't an architectural feature, so no idea why they are terracotta. These 2 things will calm it all down. You could consider texture-coating the board of the upper storey. It's a colour-embedded acrylic render. No painting for 25yr. It gives you the look of render, and can go straight onto board like you have. Unless you have rot or other maintenance issues with it that you need to replace it.

The silver will look quite good with your colour scheme. I would probably change some weatherboard for Scyon Axon just to change it up a bit. Also use Scyon Axent for architraves and wall corners. Don't forget eaves and veranda ceilings, etc. as a really nice looking feature use HardieGroove or maybe even some timber to break up the acres of painted surfaces.

Can you provide additional information...new build or existing house you are renovating? Plans or photos are very helpful to invite comments. Cheers.