I don't think it hurts at all to try a new event, and especially if you have an established community, maybe it'll be something that's entertaining that will shake up the normal order of things. I know as a member of a site, I get excited about just about any kind of event, just because it gives me something different to do with my threads. Heck, I'm just happy that there are events in general.

If you're really worried about how a new event type or mechanic would fare, the best way to go about it is to just trial it out and ask for feedback after the conclusion of the event to figure out what worked, what didn't, and if it's something that the community would be interested in again.

I often decide the outcome I want in an event, and then work backwards designing around that. I highly recommend that method, because it helps you structure intelligently towards a goal. Most of my events tend to be socially-oriented, because my goals are usually designed around character development and encouraging further character dynamics (I struggle a lot with thinking in a PVP mindset).

A really easy event I did that was very popular was a Valentine's Day event run by my character's flower shop. You filled out a set template to order either flowers, perfumes, or desserts for another character, sending it to them with a short card that either was anonymous or signed. It took very little effort to write on my end, very little effort to participate in, and yet had large story implications. My initial goal was to create a personalized opportunity for members to express their feelings towards other characters, while using my existing story tools to facilitate that.

Things like this fit very organically and neatly without upsetting other narratives, imo. Are there any types of events you'd like to steer more towards in general? People can probably share similar structures that worked for them.