Taking so long to fulfil the quest was definitely a choice, especially since finishing quickly often tended to upgrade performance ranking. But this quest had a fixed reward instead of one based on evaluation. Secondly, he really was thinking about the best way to offer mortals an entire experience.
The 49 towers in Chelsea ensured that all cities were connected, so there would be no problems going from one city to another. However, the areas far away from the cities were untamed wilderness. Lex placed actual wild animals in there - at the mortal level. However, even so, their presence added a level of danger and difficulty.
After all, fulfillment was found from accomplishing something worthwhile, and more often than not, the challenge of something is what made it worthwhile.
