With unlimited time and/or by staging the boat at a couple of places;
west down channel in April/May with a fair chance of n/easterlies...along the south and west of Ireland, over to the western isles, down to Inverness and west through the Caledonian and thence home down the Irish sea on the western seaboard,IoMan,Lands End and home.
Not clockwise so much as loop the loop !
Now that would be a trip,with plenty of route alternatives according to the in/clemency of the weather /forums/images/graemlins/smile.gif
Try, if you can, to read a book called "One Summer's Grace" by Libby Purves (the R4 presenter). She and family did it in the space of one summer - as the title implies - with 2 fairly small children. They went clockwise, and included the whole mainland + Orkneys (they did cut through the Crinan canal though!)
If it's still obtainable it's a wonderful read. My copy is held together with sellotape having been shipwrecked, but I still re-read it from time to time...
An afterthought: The Pentland Firth has been mentioned, and is often considered to be a good reason for avoiding the north coast: NOT SO, if you go clockwise, and are prepared to slip into Scrabster, just to the west, to await suitable weather with good visibility; and of course the East-going tide.
In strong-to-gale W or NW winds and W-going tide this is one of the most fearsome stretches of water on the planet, but in moderate weather and fair tide it is no problem for a well-prepared yacht and prudent skipper.
Operating as a sea-school, I used to run courses 'north-about' Scotland, in both directions. We made passages through the Pentland, or across it, by day and night many, many times. There was often a frisson of excitement for first-timers, but never any danger. If conditions were potentially risky, the passage via Scapa Flow, Stromness and Hoy Sound was chosen.
A robust boat and crew, careful planning, good timing and competent seamanship is all it takes.