I don't see why you can't do a majority or all of your RP in the IC section if you so wish.
Some people may prefer in-game it because you can do actions, have potential eavesdroppers etc. But I think if you reached out to people (aka you're in Ul'dah and you reach out to people who are regularly or always in Ul'dah) you can get the same on the forums.
I definitely think that if you plan on doing lots of RP with people here and not in-game that you supplement your RP with pictures and such of your character.
Some people may prefer in-game it because you can do actions, have potential eavesdroppers etc. But I think if you reached out to people (aka you're in Ul'dah and you reach out to people who are regularly or always in Ul'dah) you can get the same on the forums.
I definitely think that if you plan on doing lots of RP with people here and not in-game that you supplement your RP with pictures and such of your character.