Sgurr na Stri is a great wee hill, and you don't have to do a huge walk-in to get to it. You can get a boat from Elgol
http://www.bellajane.co.uk/, and provided it hasn't rained a lot in the preceding days which would make the stepping stones problematic, it would be a great adventure. We saw bottle-nosed dolphins en-route. You need to ask for the earlier climbers' boat to make sure you have a long enough day, unless you think you can do it between 10.30 and 4.30 as they go over slowly telling stories about the other islands after that. Once on top, you can see the whole Cuillin range spread out.
Here is me suddenly wondering if I am up to the stepping stones, after huge rainfall two days earlier. There are two stretches like this. I'd post a link to the whole trip, but it is on another site, and the admin doesn't like such redirections