The idea is, they got raw power in their stats, but they don't have 'support' perks that give direction to their stuff. So they're good in general, but not at all in specific. A generalist, but one based on innate talent rather than many learned skills, with a bit of focus on talking to things that mere mortals would just grab their torch and pitchfork for. They also have a whole subplot going on with their pseudo-divinity, sort of like how Vint-Savoth Foresters have as their subplot
DEMIGOD- Alterately, Semigod, Hemigod, Paragod, Quasigod,
Demigods add +1d6 to all their stats, and have Religion as a skill (but to them it's just gossip)
They do not increase stats at level up though.
Demigods roll 1d12 for reaction rolls instead of 2d6, as their presence tends to be polarizing. They inspire the faithful, threaten more materialistic members of the church, and send opposing faithful into frothing zealotry, heck even animals get a weird vibe from them.
Choosable Traits, 1 per level, up to 4. Yes, you can choose multiple ancestries, though you can't swap 'em out like you can with other traits. It's complicated, for gods.
Helios Ancestry- Helios is a distant god that prayers cannot reach due to his speed, but sometimes someone gets struck by lightning and gets pregnant rather than dying. Or is blasted to bits, leaving only a baby in the ashy remnants. In any case, you were one of those babies, and can talk to fire and lightning and wield and wear it like other people wield and wear swords. It's pretty rad. You also can sense when sunrise is coming, though Helios is as oblivious to you as any other mortal, concerned only with his rivals, the Moons.
Our Lady of Gardens Ancestry- These babies are usually found under the neatly-trimmed vegetable patches of monasteries. Maybe they're a bastard offspring of two regular monks or nuns, or maybe Our Lady was involved. Mutations, maimings, curses, and anything that would set your divinely arranged body into disarray simply won't stick. You probably have some OCD. You interpret patterns as hints from the Lady, but this might be pure delusion. You also get along well with domestic animals, able to communicate with them perfectly, and you get along TERRIBLY with wild ones. People are animals too, sorta.
Demurge Ancestry- Marked by the Lord of Calamities and likely scarred by a childhood of violence in the Wurderlands, you recover some magic dice upon doing something injurious, cruel, and/or destructive. Destroying monsters and scenery only ever gets you 1 die- you must attack your fellow man for more power. You also start with a destructive spell that emanates from a curious mark somewhere on your body.
Ibn Haur Ancestry- The headless old god of Saresare, fallen from common worship with the coming of the Law, you probably grew up a changeling. Your own head is both detachable and replaceable, and you can steal the heads of other creatures without killing them, though they'll be in a right pickle bumbling about with no head.
Unknown Ancestry- You've got the blood of something from BEYOND in you. Gain a mutation every time you level up, and for each level you have when you take this. Or, come up with something else- absolutely anything could exist BEYOND, or perhaps even closer.
Mortal Coil- Take a level and perk from another class. Hey, you can't just rely on your bloodline for everything unless you're a noble.
Divine Presence- When confronting things that would be appropriately awed/cowed by the divine, roll your charisma with advantage. Enemies likely roll morale with disadvantage.
Celestial Tongue- Language barriers do not exist for you, and spirits and monsters are much more likely to heed you when you attempt to speak to them.
Faith In Me- Though it is absolutely heretical, you can encourage a cult to form around you. Investing money in this institution counts as squandered wealth but it is by no means squandered! Develop your very own blasphemous sect sure to enrage those priests of the three gods of the Kindgom of Day and the Saresaren Law alike, but hey. Cultists!
Spark- You may perform miraculous feats that defy common sense if you do a stat test using 3d6 instead of the usual 1d20. Like lifting an entire ship or something. However, this comes with miscasts and dooms on doubles and triples.
1- Your miracle attracts your demigod cult. They are naturally quite opposed to your reckless
adventuring and will probably try to drag you off to be enshrined in a temple.
2-Your miracle attracts a nasty cult that wants to sacrifice you in some obscure ritual, probably to a moon.
3-Your fragile mortal form cannot support the divine power manifested, and you take whatever you rolled as damage, and though it won't deal any lethal damage, you are KO'd if your HP hits 0
4+You are exhausted from your feat and cannot Spark any more today.
1-You have attracted the attentions of your Nemesis. You really aren't going to like what it is.
2-Your Nemesis is coming to destroy you. You can try to defeat it, but you won't. Escape is your only chance.
3-Your Nemesis will come a third and final time. You must either ascend to a higher form to hope to defeat it, leaving the mortal realm forever, abandon your Demigodness and become a level 1 other class to sink beneath notice, or die trying to compromise.