North Coast 500 (NC500) is currently on a lot of folks radar. There have already been threads on here about it. Remember to do the “wee mad road of Inverpolly” though – the official NC500 route bypasses this buit. To fit in with a weeks riding you could shorten it by cutting south at Tongue, through Alltnaharra (great B&B) to Lairg, Rogart (Sleeperzzzz “B&B”) and over the Struie to Alness.
Or take the train to Kyle and work your way up the coast.
There’s some on-street parking at Bellfield Park (round the back). It’s a quiet residential street and I often leave a car there overnight.
In general the Highlands are great for cycle touring. Roads are generally quiet (though the Inverness-Ullapool road will see peaks of traffic as ferries arrive/depart). Lots of singletrack roads further north and (as feedback from our hire customers is showing) drivers are mostly patient and courteous.
Don’t forget to carry food with you. There are few cafes/restaurants/shops. It’s always best to plan ahead.
Buy Nicolson Maps Road 1.
If you get more sorted on ideas, PM me and I’ll see if I can provide some further info.