I live in Connel, near Oban on the west coast of Scotland.
I can thoroughly recommend a trip to Lunga, one of the Treshnish Islands.
There are organised trips that involve a ferry trip from Oban to Mull then a bus journey and a boat to Lunga and Staffa (famous for Fingal`s Cave).
The most important birds on Lunga are puffins and there will be huge numbers of them there just now, many of them approachable to about 1m! Also shags, guillemots and other sea birds.
If you go to Oban please also look into the Thursday sailings to Coll and Tiree for a visit to these Hebridean islands.
There are also trips to Iona which is very photogenic.
Farther north, consider Handa Island to which there are boat trips. The island has good sea cliffs. I`ve also even seen a lizard there.
However, perhaps the most spectacular place to see birds is on the day trip to St Kilda. After visiting Hirta, the main island, the boat we were on went past Boreray, a huge sea stack which has thousands of gannets. Be aware that this is an expensive trip and needs a lot of planning.
For more ideas look at the Scottish Wildlife Trust website.