Hey Al
@BigAl737 , good to know you're considering this.
Tony has already given some good advice.
First up weather. May June is the time I recommend people visit. It's not the warmest but given we are never really warm, that should not be a big consideration. The hours of daylight are immense and if you've never experienced 18 hours of daylight and a further 2 of twilight, it's worth it. September is warmer but wetter. October can be cold and wet. It's just the luck of the draw.
Culturally, Edinburgh and Glasgow are worth visiting. There's a lot going on there and happening. Museums, galleries shows bands etc, are all concentrated in the central belt. Watch out for the Festival in Edinburgh. Prices skyrocket as it is so very busy.
Walking wise, the mountains are amazing. They are very very old so not very high but do not be fooled, if you are walking in them you need to be prepared. With nothing between the tops of the Cairngorms and the arctic, blizzards can happen at any time.
The distilleries are worth a visit. I'm sure if you end up in Aberdeen, tony or I will drive the two of you out so you can both enjoy a wee dram!
Castles are worth seeing. Although there are the two biggies, Edinburgh and Sterling we have about 130 in the north east. More fortified houses than full on castles but good none the less.
Additionally, the North east gas a lot of Pictish and other ancient sites. More stone circles than you can throw a stick at along with burial mounds. All easy to get to by car.
Travelling around Scotland can be done by public transport or car. If you choose not to drive you are limited to the cities, central belt, and east coast as the west has relatively few busses. The far north has practically none!
If you fancy a good walk then consider the north coast 500. More intended to be done by car or bike you see some stunning scenery and horrendous roads!
Talking of roads, be aware that distances are greater than you expect. Aberdeen is 140 miles from Edinburgh but that's at least a 3 hour journey. Bear this in mind when working out where you are going. A roads in Scotland are generally 2 way once you are off the main routes. It means they are interesting to drive but you just need to get stuck behind a tractor and the journey can seem very long.
Of course, Susan and I would be delighted if you wish to stay with us for a few days. I can guarantee no ASL chat while the ladies are present!
Feel free to ask about anything. I'll also post a link to the Scottish ASL group as currently both your replies come from Aberdeen in the far North East. We have folk in the Borders, Edinburgh,Fife, and Inverness but no one in Glasgow. They are a strange lot there...