We may consider this in future but really, we can't put a Maiden to every map. That's why you have the Portal skill and Maiden's Tickets in the game.
Yup we do, but for so many maps without a maiden having only 5 spots to make a portal at ... well, still at a loss and lot of walking needed to get where you need to
On another note:
Is it possible to make/change some NPCs on couple maps so they too have store?
A lot of maps dont have an NPC with such feature, and if you dont have your backpack maxed out (which takes a lot of Reales to do) it gets hard to keep all the stuff you need when doing a couple quests on one map, if that map does not have an NPC you could drop the rest at and take it from later.
Just a suggestion, while the team has some work to do with the next update maybe give this a thought too
Life's already too serious
Don't make your games be the same
They are suppose to be fun