Having characters who are always eye-candy is restricting.
The same strawman over and over again. It's not about ALWAYS eye-candy, it's about SOME eyecandy. There is a massive difference, and repeating this trite argument over and over again doesn't make it any more representative of the requests at hand.
Does they have to look young (20-30) to beatiful? Should they have no flaws or dark past, because someone might dislike whole character, because of these flaws or their past? If yes, these things will limit developers and characters they can create a lot.
You're mixing in a ton of issues without any real relevance to the matter to paint the requests as more restrictive than they actually are. I think you'd be hard-pressed to find people who would honestly say that Flemeth (as in DA2) was not beautiful. Also, once again, I and most others seem to be talking about simple visual beauty. We are long past discussing the issue of attractiveness (including character etc) vs beauty.
but if creating one's eye-candy makes my eye-candy (like Cassandra) eye-sore well I wouldn't be too happy about it.
I understand that. Right now I'm sticking post-its on my screen when Cassandra appears (this statement contains 80% joke). In any case, yes, you are right when it comes to defined characters. We are at an impasse there because you love Cassandra's look and I don't, and I want something else and you don't. So you win atm thanks to the developers' support, I hope to win next time. (Though tbh even if they did turn Cassie into a supermodel, her character would still ruin it for me, so it doesn't really matter all that much...)
This whole argument falls flat though if there are ways to support options, e.g. with regard to armor or even companion customisation like in SWTOR. Nobody needs to have eye-sores, and everybody can have eye-candies, if not everywhere (which could indeed be boring), at least in some places. And considering past mods, I don't think it'd involve all that much effort to make properly either.