RoM needs advertisements. I don't mean they should advertise their game. I mean there are plenty of companies(cars, cellphones, insurance, etc.) that would probably pay RoM to advertise their content. The smart way to do it, would be to have it not be in-game(like gold sellers), but instead in the login and load screens.
For instance, you click the RoM icon to start ur game, the window opens and it's split in half. On the left hand side, a video ad plays (a cell phone ad, for example). It should be either 2 15-second ads or 1 1-minute ad (muted of course). On the right hand side of said window, you'll go about logging in as normal (typing in ur name, pass, secondary pass, etc.); all while the ad(s) on the left hand side is/are playing.
Also, RoM could place various ads within the load screen, whenever you transport to another place.
Both these options would mean that the player is not annoyed by the ads.
Hopefully if RoM can make some money from these ads, they won't have to rely solely on diamond buyers and nerf all the good ideas (dia exchange npc, rune npc, owenstein, etc.).