There's always room for new RPers in the community but it's so hard to find that niche as a new guild, so many start up and gain a handful of members then sadly fade away. Or alternatively leech characters or alts from other guilds which only serves to spread the RP Community even thinner.
As Kayne rightly says there's been a decline in numbers in the RP community over the last 6-12 months. There's many reasons for this with the general playerbase declining, the game itself becoming more and more item driven, the luke warm reception to SA and the plethora of "better looking" MMOs out there, etc. etc. the list can go on and on.
All that said I had all but given up on UO 2.5 years ago until I stumbled across a BoC patrol and I'm still here.
Although the RP community more or less abides by the roughly the same RoE each guild also has it's own restrictions on skills and classes depending on their level of "fantasy".
For example there's Grd who persecute elves and mages to BoC who are more tolerant to the Vesper and Trinsic guilds that openly accept them. Along with restrictions on skills, weapons, special moves and spells etc. to try and create a level playing field in terms of RPvP.
As for why more mainstreamers don't get into RP i think the transition from going from playing as someone who can solo a para balron or better and who is a "leet pvper" to acting out a "normal" person from the medieval period with their fears, prejudices, hopes, aspirations and indeed limitations. From a situation where a characters armour and weps might cost hundreds of millions to someone who a hundred coins is a small fortune. Not to mention going from leet speech and smilies to full sentences and emotes.
I hope more players take a look at RP and hopefully enjoy it.
Good luck Lucy, you know I'm always here if you need help or advice.
