Just thought I'd run over a point or too, it may be of use to you 😉
If you're trying to design a beer, your first point of call is to select a commercial example you like, as you've done already - it allows you to pick the things that you like about the beer - maltiness, colouring, flavours,hopping, etc. If you can, a polite e-mail or chat with the brewer could yield a lot of information to help.
Next up, I like to look at the BJCP style guidelines for the brew in question; lets take your Scottish Light : we can gain a lot of info and make assumptions here too (in red)
" The BJCP style guide says: Cleanly malty with a drying finish (this tells us that the beer isnt hop driven, and will have a low FG), perhaps a few esters (esteric yeast - english ale or traditional scottish strain), and on occasion a faint bit of peaty earthiness (smoke) (clue to possible peated malt?). Most beers finish fairly dry considering their relatively sweet palate (dry AND malty ? suggests we might want a brewers invert or basic sugar (muscavado or demerara) here, and to mash at a high temperature to maintain malt complexity), and as such have a different balance than strong Scotch ales. Low to medium malty sweetness (another hint at brewers invert), sometimes accentuated by low to moderate kettle caramelization (caramels come from inclusion of crystal malts or by boiling the hell out of some wort to get kettle caramelisation - hint to content and technique). Some examples have a low hop aroma (mainly boil bops, no or small late aroma addition), light fruitiness (esteric yeast), low diacetyl (another hint on the yeast and brewing technique - low diacetyl producer, likely at a slightly higher ferment temp, 20 deg over 18, say), and/or a low to moderate peaty aroma (small quantity of peated malt if you want this charecter) (all are optional). The peaty aroma is sometimes perceived as earthy, smoky or very lightly roasted."
Ok, So what do we have ?
* Ester producing yeast strain - Scottish strains if you have them, but a good estery english should work well too (such as recovered Fullers, or a Dried London Ale strain)
* Malty but dry - likely use of Invert or basic sugars, along with a high mash temp
* Caramel - Crystal malts or kettle caramelisation - how caramel do YOU like it tho?
* Low Hop aroma - restrained, traditional english hops with boil rather than flame out additions - not gonna want 100g of Citra in the whirlpool 😉
* Peated character, but not strongly so - peated malt is HELLA powerful, so perhaps as little as 1% of the grain bill
* Warmer end of the ferment scale to prevent too much Diacetyl. Nice ferment period too - 2-3 weeks perhaps.
From here, you can have a go at your own recipe, or plug a premade recipe with any info you can find 😉
Making beer is fun fun fun 😃 lol