Hey, creating workstations and building other things is scheduled for v0.5 which will come around June next year. You can read a bit about the roadmap here. 

Magnus is a miniboss. There are many minibosses around the world. They usually give significantly more exp, often better loot and are harder to deal with. There are 2 bosses in the current version of the game.

Berserker and fallen knight are quite good to start with as they deal well with melee attackers that are troublesome to ranged characters like human travelers or elves, but require a bit more careful approach when there are more casters and ranged enemies. Warlocks can get very powerful quickly, but early game can be challenging for new players, especially since some enemies should be avoided and escaping is difficult. When you hold left shift and hover over enemies you can see their level comparison message, if you play carefully and avoid higher levels you should do fine early. The starting area is safe from wandering enemies unless they chase you, you can use that early to rest. 

For berserker I like to go either dwarf with stats 3 endurance and 3 willpower for extra protection since berserker has damage from rage, or orc with different splits between strength and endurance (full strength is fun) and warlock full intelligence to start with.