1. There are actually hundreds of possibilities of what shade of colour a troll's blood will be. There are many things that would factor into this. Climate of the area the egg was incubated in, the geographical region, the mix of genetic and coloration of the parental slurry of genes, the temperature the egg was incubated at, and so on.
2. A female troll's "breasts" are connected to her nook. The reasoning behind this one is the whole genitals thing. Trolls have both a 'bulge' or penis, and a nook, or 'vagina'. They do not have nipples, as trolls technically are not mammals and do not raise their young on milk (or at all, really). A male has a smaller nook capacity, and a larger bulge, and generally produces more genetic fluid. A female's bulge would be generally quite smaller, and produce less fluid. However, their nook capacity would be much larger, and the reason they would have breasts would be both fat or muscle deposits, and rather than a mammary gland, a sac that would hold more deposited genital fluid, released when filling a pail for a drone. (Yeah I know this one is weird)
3. Rather than the whole "landweller ears up until violet then BAM FINS", troll ears become increasingly more aquatic the higher in the hemospectrum they are. Indigos, persay, might have vestigal fins on their ears, such as ones that attach to the bottom of the ear and continue on the fin. A fuchsia blood might have a literal fin behind their ear. Only seadwellers have gills though.
4. Tealbloods and up have a form of webbing in their fingers. It becomes very pronounced in indigos, and is fully formed and functional in seadwellers.
5. Trolls have similar characteristics such as horns, body structure [like stance, walking habits, occasionally things like jaw structure] to their lusii. The reasoning behind this is that it was said lusii would choose trolls who they were able to take care of well, or had such similar characteristics to themselves.
6. Seadweller fins do not develop until pupation. Until then, they would be more like very small skin folds or flaps, or very small fins or ears. When the troll pupates, the fins develop into what they will look like into maturity. This has more to do with the trolls habitat rather than their genetics. The different styles or shapes or kinds of fins would change depending on the type of water and habitat a seadweller was around. An example of such would be deep sea water, freshwater lake, saltwater lake, fast current river to slow current river, marsh, swamp, rain-made pools, reservoirs. They develop into what would best help the troll survive in it's territory.
7. The subjugglator thing Gamzee has is a genetic disorder that only effects indigos. It makes them have very violent tendencies and habits that develop and become noticable very young into post-pupation. Rather than face-paint, the white and some of the darker grey skin on their faces is actually splotches and mutated pigment in the skin that shows up later in life. It is a recessive gene and does not effect all indigos, and is more common in males. Sopor slime has a regenerative quality that helps battle the disease, similar to how chemotherapy works with cancer.
Similar cases occur in other bloods when the whispering of horrorterrors trolls naturally hear in their sleep [rather than nightmares] is not quieted by sleeping in the slime.
8. Rather than having nightmares, that which effects trolls in their sleep is the whisperings of horrorterrors.
9. Trolls actually are generally passive, peaceful creatures. Due to many of the things that occur on Alternia however, with war raging across the universe, things become more violent. The horrorterror that is the Empress' lusus, being somewhat close to letting out the final roar [i forgot it's name] that would kill all lusii or trolls effects both wild lusii and those rearing trolls, making them much more territorial and aggressive. You must remember- lusii ARE wild animals. Trolls generally have much influence on them from their lusii, which can make them much more aggressive, violent, and angry.
10. Albinism is very rare in trolls, more common in females, higherblooded seadwellers, and jadebloods. Albinism makes it very easy to be sunburnt, or harmed by the sun in general. That would make this trait more susceptible to occurring in jadebloods- who generally live their life underground tending to the mother grubs, or higherblooded seadwellers, who might have hives or tendencies to live in very deep waters where not much light is available. As both fuchsia and jade are predominantly female, this trait would be much more common in female trolls.
Albinism would make a troll have the appearance of a rainbow drinker, without the possibility of turning the skin tone on or off, and without the glowing. The yellows of their eyes would be white, without pigment, and the irises, when the blood colour developed in them, would be various shades of red instead. Their hair would be white, rather than the usual black. This would cause most albino trolls to be culled at a very young age, though if they were to survive, there is no change in the actual colouration of their blood.
11. It IS possible for a troll to have a brother or sister, but it is extremely rare. It happens when a pupa egg has the embryo split inside. Aka, twins. It is very uncommon that it occurs, and even more uncommon that the twins would survive. Triplets are possible but it is almost completely unheard of. There are no known cases of triplets surviving to pupation.
OKAY. So these were just some that kinda came to mind and I REALLY had the urge to go on about them or let them be known. Please, tell me what you think!!!!