You can use what basically looks like contact paper (i.e. the stuff used to cover books in primary school) to make clear glass windows look frosted. Something like this from Bunnings: http://www.bunnings.com.au/handi-home-900mm-2m-plain-frosted-decorative-window-film_p3960052 However, you may want to talk to your builder first as they may be able to replace the glass in the front door for a decent price.

I don't think you can go wrong with a large timber door. The colour should contrast with the granite nicely and will even help soften all the colder surfaces. Have you seen any doors you like? https://www.houzz.com.au/products/front-doors-prbr0-br~t_10816

Side lights for sure and a straight door like To find and design pictured but I'd use clear glass, because the door is recessed which creates the privacy. Paint it white and at the same time paint the balustrade white to feature it again as was the idea when it was designed and return the front patio to red which I guess would be the original colour. Changing these great houses from original and think they look better is like getting an original XP falcon and putting a spoiler on the back because a spoiler looks good on a Porsche.

:o) and that looks beautiful too. I love the combo of your tiles, the charcoal and red. It makes me smile that we all take an interest in each others projects. I wonder if it is a combo between wanting to help each other because we know how stressful renos can be, plus loving beautiful design, plus the "dream" factor...in that we think about what we would do in a similar situation.....Seeing the whole look now.....the colour I suggested wouldn't have worked anywhere near as well as what you decided on....Hehehe.