I've got more questions - what direction does front face? And climate?

Orientation and climate are important to know.

The facade of the house is quite grand and formal so my immediate idea was a formal garden with clipped hedges, which asks another question, how much maintenance are you willing to put into it?

faces east, hot summers and very cold winters with frosts.

don't mind maintaince... just want it to look great.. does it need trees?

where do you think for the water feature?? and what for front path?

love this entrance.... http://www.oswaldhomes.com.au/luxury-custom-homes-perth/dalkeith-3 not sure if it would suit our house??

The feature trees in the link you posted look like white crepe myrtles... With the grey of your house a hot pink variety could look sensational in summer. I also like the style of paving they have used. I would be inclined to place a feature urn or water feature, as Julie suggested, in front of the three tall windows/between front door and garage rather than in the centre of the path.

"does it need trees?"

I think it will look better with some height variation, with some vertical elements.

"faces east, hot summers and very cold winters with frosts" suits deciduous trees like crepe myrtles. You'll get the shade in summer and the warmth of the morning sun in winter. The white would look lovely or as Scottevie said they come in other colours too, but be mindful of the fact that the sizes vary.

You can go what you show us on photos, just get plants, trees for your location. Look at your neighborhood, that they have, what your local nursery has.