@Magicdave, here’s my quick opinion for you:
As long as you have more pegs than things to store you’re OK. If you use a story, you don’t have to worry about length.
Reusing your pegs has been covered in multiple places on the forum and can be searched easily with reusing or reuse or just browsing the list of topics at Is it possible to reuse memory palaces?.
Let’s say you use your body as a simple set of location pegs. I have twelve in mine. The first is the top of my head. I’d start the seven deadly sins with a pride of lions in my hair. I start the virtues with sticky prunes in my hair. With the zodiac, maybe you start with Aquarius, the water bearer, because it starts in January. All you have to do is associate the type of list (the cue) with the first peg value and they will stay separate. Sin gets you thrown to the lions. Virtue is eating prunes to help digestion. The book of constellations of the zodiac are soaked by the water from the water pitcher.
Do a search for how to create palaces also for help there. My “palaces” (I use the terms pegs and stories) are large and use all sorts of methods based on which ones work best. The more you practice the better you can look at something and ‘just’ remember it if I understand you correctly.
Good luck and enjoy browsing the pages here!