All you really need is to clear the main story dungeon. The rest is optional / intended for post-game.
I try to balance the game around gaining 1 in each physical atribute and 1-2 HP per week. You can get much more (and less), but unless you really mess up, you should be able to clear the main dungeon before the first year ends.
Money is not something that is balanced yet. It is way too easy to get if know what you are doing, but it is not that useful in the end game, since most of the good stuff can be found (Mr. White's shop is an exception, but that is going to get removed once the game world gets big enough).
All trade skills give you the last skill at level 50 right now.
Most of the unlock challenges, fighting Mr. White and the endgame dungeon can be cleared in the first year only by experienced players. Everyone else will have to wait a few ingame years to get stronger, or unlock the imprint system and start with stronger character.