PMs seem to be the big demand - Rob, most sites that I visit have them enabled. In fact I think RX is the only 1 I use that does not allow it. Yes there are occassional problems but we are all adults here and don't need to be protected. The only downside is to RX due to less posts and potential for touts or competitors to use it to entice posters. But it would also cut down greatly on all the "crap" posts (like "Hey, Meyer Lansky, email me @" or other personal topics that no one else cares about)
a lot of the ideas posted are pretty far away from the focus of RX (line service, stats, etc). Probably don't want to get involved in that stuff IMO, there are plenty of other sites that do that stuff well.
Having steady sources of new content could be improved (more writers or more regular, focused columns)
Personally I have been saying RX should have a "player protection" plan for some time. Maybe it is feasible, maybe not. Lots of attempts have been made at other sites with minimal success. But that is the #1 thing a "watchdog" site can do (whether you call the RX a watchdog or not is personal preference I guess)
Does RX really want to break some ground? How about an "unbiased" dispute resolution procedure? You have an obvious bias in that you are taking ad money from some books but not others...how about getting together some "industry leaders"...other site owners, "watchdogs", intelligent posters, and maybe even some people on the other side of the counter...to allow totally unbiased resolution of issues? A "Supreme Court" of sorts. It would need to include people of varying "affiliations" to smooth out any biases, people who normally may disagree (e.g. an RX mod, Shrink, The Major, Roberto, Peep, etc). But bringing them together under 1 umbrella for dispute resolution that can be based purely on the facts and not all the agenda-driven crap would be terrific.