Interesting little things I noticed by staring at The Spreadsheet:
Genes that every single breed has are: Soil/Loam, Fade/Blend and Underbelly
Thorns are the only line-breaking tertiary that every single Ancient has
Auraboas are the only breed without Sparkle, Cirrus are the only ones that don't have Gecko or (somehow) Stained, and Everlux are the only Ancient without Blossom
When it comes to breed-exclusive genes, Cirrus obviously hold the crown at the moment, but Gaolers are actually in the second place with 2 exclusive gene pairs (Shaggy/Streak and Phantom/Spirit) and 5 tertiaries (Pinions, Scorpion, Shardflank, Weathered, Wintercoat). ngl that tert list just makes me think how great some of them would look on other breeds
On the other hand, Sandsurges only have 2 exclusive terts (Beard and Darts) and no prim/sec pairs
Aethers and Undertides have more genes than Modern breeds (141, 139 and 133 respectively)
Despite being relatively new, Everlux have more genes than Auraboas, Dusthides and Sandsurges (also Cirrus but that one's obvious). They're only 1 gene behind Banescales
Aberrations have exactly 38 of Primaries, Secondaries and Tertiaries each
Proportion-wise, Auraboas have the highest tertiary ratio: almost 40% of their genes are terts. For Moderns, that number is mere 26%.
(bear with me on this one) Aberrations are the closest Ancient to Moderns "genetically": only 22 of their genes out of 114 (~19%) aren't also met in Moderns. I'm mainly adding this because it's amusing if you consider the Aberration lore. Gran-gran might have two heads, but we're not that different after all...