I would love to help you out, since there is a lock of information as to what classes you would like to play or how you generally play I will just assume the following: You are a min/maxer and want to combine versatily with usefulness and you won't take lonewof. I will further assume that you will pick up the NPC's the game provides which are: Madora "fighter-type" and Jahan "Air/water mage-type".
So that is a lot of assumptions and they are the mother of all **** ups, but in my defence, if you had been a bit more specific I wouldn't have to assume all this.
Knowing that the npc's will be a knight and mage you could just say ok then I want to fill in the gaps myself and grab a dex based character that way you kinda have all the 3 basics down, I personally am a huge fan of the archer. Not only because I just really like that class in general (not just in this game) but in this game it's the only class that gets the maximum out of perception, has a ton of special arrows (imo 5/23 are good the others are fun but sub-par) and it will have a ton of abilities.
So that leads to me saying: "Do make yourself an archer!."
(If you eventually want tips/advice/help on how to build it feel to ask.)
As far as your second character goes, it doesn't really mind. In fact it doesn't really matter what any of your 2 classes will be, the game is suited for any class combination you see fit. I suggested a dex character because it would let you experience a str, dex and int based class right frm the get go.
The second character can be anything that you want it to be, assuming you do take an archer, you will have physical ranged, physical melee and caster support covered. So you could make another caster character. And depending on what you like, you can make a "figher-mage" type or just a mage of your own. (I suggest taking up pyro and earth as main schools on your own mage, mostly because the other mage is water/air and this let's you see all the spells in the game.)
My most enjoyable playthrough was my 2nd one, I made an archer and battlemage and they had a ton of versatility, leaving all my options open. Although I have to say I did my 1st playthrough on easy so by that time I kinda knew what to expect, so this was also the playthrough in which I optimized everything.
Conclusion/Recommendation:
Grab an archer and grab something that you yourself would thoroughly enjoy playing!
With kind regards,
Rashar.
