If you're having enough lockpicks at hand, I would recommend to work from 50 to ~76 (when you re actually able to open a lvl 2 chest) with a lvl2 paragon-chest (from an earth elemental for example). Afterwards you are fine with chests from brigand camps to continue training lockpicking. (Haven has fast respawning camps. You can get rid of the brigands with blade spirits. After hitting 84 (lvl 3 - chests) your set better for dungeon chests. (And dont forget to check the chests at banks.)
For the Haven-Quests, I would start with 49 magery. (I dont like training magery that much but going from 49 to 50 and getting a reward for it, is fine. Only that the magery reward istn that impressive.) If that should be a new char to a fresh shard, start with 49 inscription and work it for the Haven quest up to 50. Reward is an undead slayer spellbook, which should/could sell well enough to provide you with a cheap lrc-suit, a full spellbook ,a good bunch of lockpicks and some spare money for further needs.
