Going coire Grunndha is a good start, only mild scrambling to enter the upper coire and up to the Bealach a Garbh Coire. You can then head South to take in that end of the ridge with no more than easy (grade 1 or 2) scrambling. Then its fairly steady grade 2 over Sgurr Dubh na da Bheinn and down to Bealach coire an Lochan. by skirting the cliffs under Alasdair you can avoid the TD gap and go up Alasdair's SW ridge- grade 3 and a bit awkward in places. Continuing over Thearlaich involves Moderate climbing and getting off the other end is either an abseil or scary exposed downclimbing at Moderate grade. Mhic Coinnich is not too difficult (Grade 2) by Collies Ledge but it's narrow! Bypass An Stac by slabs to the left and arrive at the Inn Pinn.
Form here to the end of Sgurr na Banachdich is not too demanding (grade 2 scrambling) Greadaidh and Mhadaidh especially are difficult to traverse, andf there is no escape from this section. Mhadaidh in particular has sections of unavoidable climbing up to Difficult grade, is inescapable and cannot be bypassed without a return to the coire floor. Bidean drum nan Ramh can be bypassed on the west side ove scree and if you're not a climber this is advisable as the traverse of the 3 tops is one of the trikiest sections on the ridge. An Caisteal has a nasty section of Moderate vertical downclimbing to get off. Bruach na Frithe - grade2 scramble. Bypass the Basteir Tooth on the North side and approach An Basteir from the E ridge, but this still involves a nasty "bad step" of about Severe standard where there has been a rockfall just short of the summit.
W ridge of Gillean involves some Moderate climbing in a very exposed situation and even descending by the tourist route requires hard grade 3 scrambling.
If you want to do the ridge you should be a very competent scrambler even if you intend to bypass the climbing sections. it's not so much the difficulty as the concentration and stamina required to scramble continually in intimidating situations for hours on end with very litlle walking in between. Navigation and route finding is tricky and the easiest route is not always obvious. Having the knowledge and equipment to abseil safely (there are very few fixed anchors so also the knowledge to set these up) would be very usefull especially in case things don't go according to plan, and will on 2 or 3 sections of the ridge save you from very scary downclimbing. remember if you're taking bivvy gear that scrambling with a big pack is hard!
Not wishing to put you off but for a first visit I'd really recommend shorter routes till you get the feel of the place. A competent party that knows the ridge often takes about 18 hours, not counting the walk in and walk out. Go and recce the sections you think might cause you problems and then when you have it wired, go for the complete traverse!
Not touting for business but have you considered using a guide to help you find your feet?
Get a copy of the SMC Skye Scrambles guide if you haven't already, and Gordon Stainforths book "the Cuillin" Has quality pics and a very usefull guide to traversing the ridge.
Hope this helps! Above all, enjoy... it's magic up there!
Ian
www.mountainfreedom.co.uk