I have played the game to half way or a bit further (doing all the sidequests)
about four times once as a gunman and trice as a pure mage good/evil. I have always played to half way because after lvl 30 or so the game gets extremely easy one harm spell is enoug to bring down or seriously injure any foe IMO to prevent the game from getting boring try not to take any ofencive spells at all and maybe boost the melee skill a bit ( I used twohanded swords mainly) Also try to limit the nr of companions, they tend to make the game ALOT easier
I usually play as a mage with elven influence. At the crash site I select Harm spell, Strength of Earth, Disarm, Shield of Protection, and Minor Healing. I then play the game appling points to achive master in force, and top levels in Necromantic White, Conveyance. I add unlocking cangrip. Also do the blessing. With teleportation its fairly easy and worth the effort. Apply all remaining points to Willpower, Intellegence, Constitution. Wait and save remaining point untill after the final blessing. I usually place a couple of points to melee after the blessing to get master in melee. There is a fantastic sword in the void worth it.
IMO to prevent the game from getting boring try not to take any ofencive spells at all and maybe boost the melee skill a bit ( I used twohanded swords mainly)