Chanonry Point for Dolphins, get there at least 3 hours before the high tide and wait all day (no need for a boat trip - pics in my facebook page)
Mull for White Tailed Sea Eagles at Grass Point, and Pennigael for otters (although they are quite common around the coasts of Mull and Ardnamurchan)
Knapdale for Beavers and there's a B&B nearby that has resident Pine Martin.
Loch Garten visitor centre for capercaillie, crested tit and red squirrel. there's a fishing pond at IIRC Rothiemurchus Estate that Simon King staked out to get fishing male osprey.
slightly further west you'll find breeding Slavonian grebes on Loch Ruthven.
but you can also get fishing osprey at the Lake of Mentieth, a short distance from Glasgow.
Inversnaid and Rowardennan areas of the east side of Loch Lomond is great for nesting redstart and pied flycatcher, although they are fairly widespread in the atlantic oak woodlands.
St Abbs Head on the Berwickshire coast is great for nesting seabirds - gannets, kittiwakes, razorbills, guillemots, but there's also the Isle of Lunga & Isle of May both great for puffins, and Troup Head is another good place for gannets and auks.
Black guillemots can be seen in almost any west coast harbour, and many on the east coast too.
each location deserves at least a day to get the pics - you know wildlife, it doesnt always show up on demand.
do you have at least a 300mm plus tc's?
thinking about all this, I'm actually quite jealous. might start planning something myself.