It's been a while since my last Like/Dislike repost. There are only a few left in the series, so we might as well collect 'em all...
LIKE: RANDOM ELEMENTS
Give me some charts to roll on, and I'm happy for hours. Or, in the internet age, give me a way to generate weird modern-Cthulhu items or maybe some old-school fantasy henchmen and I'll make my own fun.
It's not that I lack for ideas. However, the beauty of randomly generated stuff is that it forces you to consider things that you otherwise wouldn't. Integrating your own tastes/biases with those of an impersonal list can lead to really cool things that you would, by definition, never have thought of on your own. For instance, I don't much like time travel (see below). But when this nifty random Champions character generator gave me a supervillain with Summon - a power I would never, ever use on my own - it sparked all kinds of ideas. So now I have not just a superintelligent apeman from the far future, but I have his time-traveling court and a the outline of a future history and even some thoughts on how medicine will evolve in this setting.
Seriously - randomly generated game elements are awesome. They force you to work with things that you probably wouldn't even have thought of, much less tried. I can't go so someplace like Chaotic Shiny without making a couple of cultures or artifacts. I love fooling around with Hexographer's free map generator. Using random elements is like having access to other GMs' brains. And who wouldn't want a big pile of GM brains around the house?
DISLIKE: TIME/DIMENSION TRAVEL
My superintelligent apeman nothwitstanding, time travel and dimension travel are usually excuses for cheap, lazy storytelling. They're a way to say "what if?" followed quickly by "just kidding!" When used in roleplaying games, in my experience, they're usually used for one of two things, neither of them being very interesting.
First, as an excuse to fight something cool, like dinosaurs or robotic Schwarzeneggers. I'm not opposed to cool fights. It's just that there are other, more creative ways to get them into your game. Saying that a rift opened in time and X stepped out is just weak. You can do better.
Second, as a halfhearted way of exploring what happens if Things Go Wrong. Time/dimension travel plots often boil down to "here's an alternate version of your world, but the bad guys are in charge." You go there, fight some bad guys, maybe fix some stuff - but it's not your world. It doesn't really matter. Even if you screw up, the reality you know isn't in any danger. These plots rob roleplaying of one of its best elements - the ability to show how PC actions have consequences on their surroundings. Not on "some other time's" surroundings, not on "alternate dimension where the Aztecs won our Civil War" surroundings.