Very interesting ideas, but if the devs were to use it, they would need to find a way to make it simple enough that it is useable.  So what I imagine is that you would click on one of your offspring and a menu would pop up in which all of your major opponent civilizations would have an opinion score toward the viability of that offspring as a marriage option to one of their own.  Then you could click deeper to assess what variables are specifically involved with that decision (if they think your kid is gorgeous, but are simply assholes who are demanding, you may not want to waste your super model on them.)

Breeding a hideous half-human that serves my interests pretty much fulfills one of my life goals. I think doing in a computer game will just have to do.

I want humans with cat ears, fangs, cat tail and pointy and hard like steel nails. Shapeshifting secondary abilities welcome. If mating doesn't allow such thing, I would need some flesh sculping abilities/magics.

Ewww, pureed meat. Wait...kitty-people would love that!

I actually envisioned different people seeing their own version of the model for everything that isn't completely new. We'll see....

Yes, folks around here taught me that name. I just thought the plain pun was irresistable. Plus, even though I appreciate open system design very much, I'm not happy to see so many beta critiques and suggestions dismissed with some kind of "well, mods will fix that" answer.

Oh shit... why you gotta say that?

"Excuse me ma'am, I think I've got an arrow for your bow."

"You must be tired, because you have been running through my kai'mel all night long."

"My World Tree also connects with living organisms..."

"I don't bite... but my spirit animal..."

Ughhhh....

Should I suggest that if you dare to mate with a succubus you should get stuck in the city permanently due to being unable to travel away for your... milker? Plus lose some stats points due to exhaustion? And increased spell failure chance due to distractions?

Really, such a thing would really need high magic (not to summon but to protect yourself + dominate her so she behaves like an obedient doll and not a devious being of utter evil*... which is what people thinks when talking of summoning one). Maybe some Essence cost (Essence as in the type of Essence used to bring land to life).

Next, we have polymorphed Dragons mating with the Sovereign! Hey, actually, I think that the idea of the Sovereign mating with "non usual" creatures can be interesting as long as it's done well. And to find such an special wife is a good quest by itself.

* and lust, yeah, lets not forget the favourite part, right?

Mmmmm, perhaps we could have the sucubus just sit next to our throne wearing a colar and nothing else to distract ambasadors? Summon a sucubus to go mess up some other channelers family? if he has a teenage male kid then a succubus would have a 105% chance of eating his soul.

My point though, is that i don't wanna be stuck with some a single, boring wife. I want a harem filled with demons and monsters and magical beings and things so bizzare they don't even have names. Forget family, where is my menagerie?

Not really? it has spoken, now it must be done! The tough aunt with the cigaretes, the good looking one that you know you will actually end up with, but is going to a distant high-level college. The one with the glasses and gaint boobs. mmmmm. Makes me want to go reread some.

Perhaps we should have a way to make lesser children who are not heroes, just high-stat monsters?

OHHH, can we get gene-warping powers? Start with monsters, breed some kids, warp and twist them, end up custom nightmares? There is already code for our heir genetics, but could we apply it to trying to breed super monsters to fight for us? Forget recruiting pikemen! I can just use my army of 8 armed 10 foot tall scaled vat-grown troops!