Just signed up here, so be honored to take my first post! xD
It really depends on the type of RP, and the type of audience you're catering to. I mean I've tried organizing an RP with the average age of players being about 13, and frankly it doesn't work unless there's some sort of system in place to prevent people from playing the hero.
Could be wrong, but people who are more reserved and realistic/faulty are either experienced RP'ers, or people who are of certain age. More often than not, people who have seen an RP ruined by bratty 13 year olds who want to be the solution to every problem.
With a good group though, stats are unneccessarily, but online you usually end up with more 'randoms' than you do friends.
To be perfectly honest stats aren't my thing, they slow things down, and make things move clunkier. They work in some instances, but I'd rather write, than calculate, and stats are restricting for both better and worse. Overall I just tend to avoid RP's that are combat oriented since that seems to be the main user of stat based RP's.
Stats can work, but as Acacia Sgt said; it's need to be adapted constantly.
And more content doesn't always equate to a better system. Simple and effective is the best way to go, but on the other hand it needs to be interesting or rewarding enough to promote interest. If people start seeing stats as a hassle, scrapping the system usually isn't enough to continue the RP as a drastic change like that makes participants question DM/GM competency. So it's probably a good idea to refine and perhaps even consult with potential players before actually implementing a stat system.
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How you deal with HP=0 is also dependant on the RP. In most cases it's better to just go with a knock-out (KO). But there are certain types of RP's were a death is more suited. (Dungeon run, D&D style thing). In most cases though, it's important to respect that the characters belong to individual participants, and killing them off without at least consulting their owners will result in unhappy people. xD
Not really sure if this was just a general discussion thing, or an attempt to test the waters for a planned RP :P