I have to agree that a game with character customisation as a strength, shouldn't allow respecs - or at least it should be quite limited.
That way, you feel like your development choices have real meaning and weight, and it prolongs the life of a good game - because you WANT to experiment and see how the game plays with a different character.
But it's a balance thing, and some games are not strong enough to be able to carry this - and I don't think Two Worlds can do it. So, allowing respecs is probably a good choice for that game - though no developer would want to realise that about their own game.
Arcania is similarly weak overall, and you wouldn't want to stop mid-game to experiment with a new character, because there just isn't enough variety to make more playthroughs worthwhile.
Back in my Diablo 2 days, I could experiment forever - and I LIKED that. I restarted countless characters, even for the most minor variations - because your ability to do damage and what not mattered so much. It became almost an obsession to optimise my builds - and I'm sad to see so few games these days, where a clever build is rewarded.
Also, a game like Fallout 3 - which is quite different based on how you develop your character, would be hurt by allowing a respec. It would nullify the work and planning you've poured into it, and I personally wouldn't want to replay it if I could just experiment with all skills in a single playthrough.
I know modern RPGs have become a lot more lenient in this way, and some players view it as a punishment that they have to start over. But I think it's quite the opposite, actually.
A game where your planning and character prowess truly matters, is a gift that is so rarely given these days.