Although the suggestion might make some players do all four daily but a large number of players will be affected badly by it. Dailys are fun but sometimes you don't have the time or simply can't do a mission because of some other factors.
These are some scenarios that can happen after a change like this:
Chakra med getting a farming mission but is not able to abandon it or has to wait for his friend to come online.
A new lowbie player gets a spy mission in a village but that village guards its entrance with a group of level 60 players that the new player cannot pass through whatever he does.
Getting guard duty when you don't have that much time to play.
Getting spa mission which gives low exp as a high-level rogue.
Getting the same mission twice (Example: Getting blood puppet and then getting blood puppet again)
Getting waging war at a dead time zone where no one is online and being forced to kill lowbies in the farming area again and again to complete it.
A new player gets a mission he doesn't understand or can't complete but is not able to abandon it. (Example: Getting finding the cat mission but not able to complete it)
The idea overall is good but you will first need to change a lot of missions and buff the exp they gave to make them worthwhile to do. also, abandoning the mission is a really helpful feature for new players who are still learning how to play.