Like in "real" wrestling, E-Wrestling mostly depends on your mic skills. If you can't write a good intervue then you're out of luck. There are several ways to have intervues, I'll do my best to go into them as muck as possible.
Email to Email Tips
Sometimes when someone makes a comment on your wrestler the first thing that you think of is replying with a one or two line comment. THIS IS A BAD THING TO DO!!!!!! When you reply to a RP always remember to put it in a RP Format.
One tip that is important no matter what type of RP you do is always be original. Don't make all of your RP's sound the same and above all, don't cut/paste "you suck" a thousand times and call it an intervue!
Mass Mailing Tips
The only problem with mass mailing is that it makes it easy for an opponent to ambush you with fifty RP's on the last day. The only advice I can give you to avoid this is to cream him with RP's the whole time and hope it's enough. Some E-Feds have rules that say you can only RP five or six times a week and that provides some protection from ambushes.
Message Board Tips
Most Message Boards and Guestbooks allow you to use HTML tags. HTML tags let you use some great visual effects in your RP's.
Don't make every RP look the same, they just get boring after a while and nobody reads them.
Never make one or two line RP's, always make sure reply's are in some RP format.
Don't just have your wrestler talking, use backgrounds and be descriptive.
Don't just ramble on, talk about upcoming matches and fueds. Make your RP's interesting and fun to read.