Continents and Island Framing shorelines

[Kellerica]

In my opinion, the scale often comes as combination of both the things within the shoreline and the shoreline itself. A large landmass with tons of small mountains feels bigger in scale than one with a couple of medium sized ranges, and so on.

I'd look at maps of the real world on a global scale for inspiration. If you want to do a whole world map, it could maybe be a good idea to emulate a the certain kind of distortion you see on some map projections? Not really an expert on this particular area, but it's just a thought.

For my two cents on the shoreline, to me one of the key things of making the scale feel larger is the implemention of tiny little islands. If you have large continents, you'll want to have small islands around them here an there, hugging the shoreline rather closely. If there is a large archipelago, don't just draw ten large islands and leave it there, but fill the gaps and and the edges with lots of little ones.

Behold the extremely crude and ugly example I whipped up (I don't have my Cintiq at the office and I'm dreadful with a regular pencil these days, but bear with me). To me, getting a shoreline to go from point A to point B immediately makes me think of larger scale.
shoreline.jpg

Obviously this is just my personal view, I'm more of an artist than an geography expert, so take it with a grain of salt. But a little something to think about, at least.