This limitation isn't necessarily a big deal - and it will depend on how the abilities interact. The key is that you have interesting and hard choices - and that every ability has a place.
That said, nothing is worse than 32 abilities that are all equally useful in all situations. I love quirky stuff that only works for some characters in specific scenarios - as long as they're effective in that instance.
One of the issues of modern game design is the obsession with scaling and simplifying how players progress. It has become the norm to make all choices effective and obvious - which means there's no foundation for interesting strategies.
Also, while some games do retain interesting tactical considerations - that's only half the fun of combat. Without the strategy - you're left with a lesser game.
The original Dragon Age was very simplistic EXCEPT when it came to magic. It had a respectable selection of spells and they worked well together. But if you were a melee or ranged character - you had but one or two choices overall, and the rest was just following a clear path. Your role was extremely simple during all combat scenarios as well.
So, I very much hope they expand on that. But we'll see.