SPOILER ALERT!!!!!!!
Magick = easy
Pure melee = easy
Tech = more difficult, but more fun in combat
Good combo is: Tech + Throwing + Dodge + Firearms (add points to Perception, but don't overdo it, study schematics that allow you to make thingimajigs that raise your perception or go for Disarm Traps skill and get the Trapmaker's Spectacles).
Good stuff to study: Electricity, Smithy (Featherweight Armour rocks) + Molotovs (you don't need more than that, they are excellent when you are being overrun by foes, it scatters them into all directions) + Poison antidote (if you have to rely on Virgil to do it, he might cast spells on you until he falls down from fatigue.
You can make the awesome Tesla Gun if you study Electricty and buy books at Tarant University (Gun Smithy).
Limit your followers. Take Virgil if you're new to the game and maybe Sogg Mead Mug from Shrouded Hills (add onepoint to Charisma to get him to join you). Later in the game you can swap him for Sebastian ffrom Tarant, if you feel like it.
If you go Tech: give Virgil bandages because his healing spells will stop working on you once you become too Tech oriented.
Tech: lockpick might come in handy. I always pick it for the extra quests + XP points.
Also: don't waste points on Intelligence if you're going Tech. Buy Potions of Intellect from gypsies instead, they add something like 10 points to your INT for a brief period of time, but that's enough to learn a schematic and/or make a new gadget. Use the books from Tarant University to make stuff you didn't study (found schematics).
Magick: what the other guy said: Harm is useful troughout the game, and the first spells from certain colleges (the ones that raise certain stats) are very useful. Add Teleport to that. Thieving is nice too for Magick users, since you won't need as much cash as a Techie. Think about a back-up weapon. Melee is great if you don't have many followers, but if you do Bow can be good too (although boring after a while). Magick users + persuasion + backstab + prowling = uber-character. Summoning college is nice. I once defeated the end boss with nothing but Vorpal Bunnies and didn't have to lift a finger myself. Fun times.
Also go for the dog, he's the best follower in the game. You and the dog = perfect combo à la Vault Dweller+Dogmeat. You don't really need more, but if it is your first game, bringVirgil along 'cause his story has some nice twists here and there.
Damn... now I feel like playing another game of Arcanum... Damn you! And it's your first time and all. You'll fall in love with it or you'll hate it. There is no middle way.