To plan?! Plan for what?? You just arrive and fight some big boss. Even a newbie Mage in a sorcerers suit has a chance for a drop now.
You need to give them more credit than that. It's not as easy as it sounds. Perhaps a little bit of enlightenment will help diffuse this subject. I've never been an EM so what I say below may not be 100% correct.
1. EM comes up with a plan for their events from story building, dialog, what monsters to use and what type of skills, the loot if any, location, design all that takes time in advance.
2. Then that plan gets submitted to someone else for approval, not sure if it's still Mesanna since she is now the producer and very busy with other things. But this someone else/s has to take time to build this story, create the settings, items, monsters, etc... and that takes time because all items to them under creation mode looks different than our normal game play (i could be wrong here).
3. So think about 15-20 events per week on average in all of UO and if all the designs and creations goes to 1 or 2 people to do, you can imagine how much time this takes up.
4. The EMs are only paid certain hours per week, they are not full time. But if you count the number of hours they devote to the creation of events which is directly proportional to the number of events they hold each week/month it looks to me they are working 2-3x on what they are getting paid for. And if they are getting paid $10/hour, for the amount of work they do, they are really getting paid $3.33/hour. Based on that alone, they deserve all of my respect and will never hear a complaint from me.
5. Not all events are for everyone, I find some kind of boring myself but others love it just fine. So it's different strokes for different folks. You may experience more of this if you only play one shard which is why i play on many shards so that while I may miss an event here or there I am sure to catch one somewhere else and if I don't like the content I can wait for the next one. It's all about how much you want to invest in this game to make it worth your while and keep it fun.