Classes sure ...
Companions maybe ...
Content ... this is tricky one, bcs everything is content ... but if you mean new locations or story ... no chance.
There is little chance for some sidequests tho (for example that stuned druid in secret passage us quite unused), but i presume that chance is also pretty small.
Same as level ... that one seem almost impossible, since we were multiple times and repeatly warned about level cap in EA ... i presume that is safe to expect level cap in EA.
