In reply to Cadairmanuk: Unfortunately the one thing the 'gorms doesn't really have is easier ridges.
The easiest buttress route to get you started is probably
Jacob's Edge 110m II * on the Mess of Pottage.
I'd also perhaps look at Coire an Lochain as it has some fine open buttress climbs.
The Milky Way 100m II/III ** is probably the easiest of the better non-gully routes in the Northern Corries. You then have
Ewen Buttress 90m III ** and
Sidewinder 100m III,4 ** which are both very worthwhile.
If you want proper 'ridge routes' then other than the fun but extremely escapable Fiacaill Ridge, they are few and far between. The only one that springs to mind is
Angel's Ridge 300m I ** on Sgor an Lochain Uaine which is fairly easy.