I tried performing in english once during my first year as standup comedian. For many reasons, like "It's hard enough getting gigs in swedish", I haven't done it since. But things have changed. My performance onstage is better, if it wasn't I would be a bad and stupid comedian, and there is a few more places in Sweden to perform in english.
But there might be some more work to do. Some of my routines contains a lot of refernces that are localy swedish. Trying to translate them with new, international, references would just be sooo hackish. I need to write new material. Which isn't that hard. I know funny.