regarding spawns and claims, i would use some kind of trigger, like treasure maps with time lockouts, i'ts not the kind of open world i would like to have, but it's a way to avoid complains from the ppl who "dislikes" competition. on the other hand we could also have bosses (even as fate), in dangerous open world dungeons, that drops good and valuable gear with a low drop-rate, this kind of bosses could drop tomes as well.