For a cheaper, faster and possibly easier option, take a look at this for some inspiration. The lighter colour of the walls may reflect more light and be a stand out feature of your home. Click on the link and scroll to the image of the polished timber floor with the timber wall and ceiling. Polished timber floors with timber wall paneling

If you want it to recede into the surroundings use a dark colour such as Woodland or Monument. Use it on walls and roof. Using it vertically and horizontally would add a nice feature to it when up closer. The hardwood for trims, architraves, etc. would look fantastic, in particular if they were kept oiled rather than left to go grey.... A light colour would mean the dwelling could be cooler in summer perhaps but shading from tree's may work just as well. If a light colour was used it would stand out from kilometres away.... not ideal at all.

I reckon you should go for a bright colour rather than the greys. Greys can look a bit boring after a while. Mainly due to their popularity as every second house I see is grey and just about every house I design the owner wants grey..... A client recently used 'Vanessa May' with Monument roof, facias, etc. and windows. The architraves in white. 'Vanessa May' is a mid violet and I got to say it look's bloody great! It's a similar size cottage as yours as well. My last client is using Dulux 'Pink Poppy' on their renovation and addition! However the job I started today has already been specified with a combination of greys...... That green you have is a great start.

Dont rely on google images, they are heavily edited and inaccurate, definately order swatches for accurate comparison. Below is a photo of Dulux Elements powder coating swatches which I have in my office - in the photo you can see (and from my own perspective of this colour) up close Surfmist is definately not 'white' but search the images on the web and yes it looks white (FYI first colour is 'Basalt', second colour 'Surfmist', third colour 'Black' and fourth colour 'Monument') Below also is one of my company's recent projects, chairs in Surfmist and tables in Monument, but looking at the image you'd swear it was 'white and black'. Before you decide Id suggest getting the actual powder coat swatches from Dulux which you can order via their website and then you can compare them and decide. Note: Colorbond Surfmist / Monument and Dulux are the same tone. Good luck!