One of the most difficult things for new players is knowing where to go next. Rose starts off fine in that respect. You begin your journey in Adv Plains, then move on to Luxem and then Zant. It's pretty straight forward and there is really only one way to go. Monsters' levels increase as you move towards Zant, which is what you want.
From Zant on, things get a bit blurred. There are always a few different map options and there is no clearly defined path for progression. One of the best features of Rose is the fact that you are not locked into playing one way but people still need some guidance. This is true even for players like my friends and I because the monsters here are often on different maps than they were at our old server and also they are at different levels.
So my suggestion is simple. Whenever you enter a map, the name of the area is shown for a few seconds. Part one of my suggestion is to put the level range of the mobs under the name of the area like this
