No one is going to throw you off for expressing your opinion in a correct and polite way.
But is AV3 that similar to the previous series?
If you say similar characters, I cannot deny it as for all RPG games, fighter, mage and healers (maybe also rogue) are the universal classes, you find them in most games.
Similar skills... well, characters in AV3 has almost no skills, that means, different from other Aveyonds.
And considering plots, I think AV3 is very different from any of the series. The places may be similar but it is quite fine since they are redesigned thoroughly.
It isn't that disapppointing, in my opinion.