Making it to host events on time never hurts, but a big key is analyzing what activities get you the most per time/energy invested. An example might be a Ride-A-Thon some people might spend the whole time riding it, but perhaps when you closely, the sprees you might trade them are worth less than spending that same amount of time in a mini-game for credits. Leveraging events like double credit or competitions can be wise as well. Good trades are smart too. In Maple Story, I used to keep an excel file of the prices of everything. I'd write the item down, and then the highest value I'd seen it sell for that still makes sense. I would set that as the minimum, and every few weeks, I'd go through every shop on the server and update it. It helped quite a bit. I have to wonder if the better traders do something like that in credit sprees or something. Of course, we have much few items, so updating more often might be in order.