OK, so this is what I've come up with:
DAY 1 (Thursday 29 April).
- Morning ferry from Ullaport to Stornaway.
- Collect hire car at lunchtime.
- Visit the standing stones, the blackhouse museum @ Arnol, Shawbost beach
- Drive to Kneep. Camp in Kneep.
DAY 2 (Friday 30 April)
- Have a walk around in Kneep, then drive to Harris.
- (weather permitting) Visit the Eagle Observatory
- Take a circular drive round South Harris, getting first impressions, and a bite to eat at the Butty Bus
- Find a place to camp, probably Luskentyre
DAY 3 (Saturday 1 May)
- Ferry over to Berneray
- Half a day's walking in Berneray
- Drive to Balranald, stopping to walk up a random hill along the way
- Camp in Balranald
DAY 4 (Sunday 2 May)
- Have a walk round Balranald
- Drive south, doing a little circuit around Loch Bi and down to Daliburgh/South Lochoisdale (eating at the Co-op), and 2 nights accommodation.
- (weather permitting) a round at Askernish golf club
DAY 5 (Monday 3 May)
- Visit to Eriskay
- Possible daytrip to Barra
DAY 6 (Tuesday 4 May)
DAY 7 (Wednesday 5 May)
- Head back up to Harris
- Camp on Harris
Day 8 (Thursday 6 May)
- Spend a full day enjoying Harris, according to the favourite spots I saw on the way down
- B&B on Harris
Day 9 (Friday 7 May)
- Visit the knitting muesum