Unchangeable filters or filters maintained NCWest side will simply not work at all due to how easy it is to circumvent for fighting RMT spam.
They change domain, they use "alternatives" and seems they are very creative in bringing their spam to you even with these filters without being filtered out.
Clientside filtering would have been one method because RMT companies will not be aware on anything you setup, sadly which is now useless because they now have been triggered to go alternative texts.
Personally i would prefer to have whitelist chat on PM for one, only allow those to PM me which i agree on so i can hold normal conversations to people without having to work trough bot spams every minute from different characters.
Settings possible:
allow clan
allow alliance
allow friends
Custom unknown: only allow characters level 85 or higher, ask first before allowing Private Message
Last setting will do the following: a level 85 or higher can PM without restriction but anything below will show a system text with a click able icon to allow or deny, no action should be deny per default.
Example: "NewPlayer wants to send you a private message allow (
http://www.google.com) deny (
http://www.google.com)"
Denied is permanent and should function same as if person was blocked except just for PM, same for allowed.
It will not fix all the problems but at least the private message function which is a very important tool to talk to certain people uninterrupted by normal chat flow, RMT spam bots are disrupting this flow and might even cause private conversations with sensitive details to go to a different source then the intended receiver.
Also to be ahead of certain imaginable problems this system should also be implemented separately to work for mail in a similar fashion.
Also if the source is left unattended these will only become worse and more aggressive, see example with how they where making town chat useless with the huge amount of rolling spam.
These RMT companies do not have moral limits they will push their stuff trough everyone's throat at the cost of both player enjoyment and server stability.
Town spam is not the only problem, look at xp areas where they level their spam toons with 10 automated characters per mob and they are becoming more and more aggressive by also having PK bots which fortunately are easy to dispatch of with a strong character but i know people who try to level on their first character or who only have a low level character who just can't make it into the quest area because they get automatically killed every time as soon they port in and who rely totally on having someone strong clear out the automated PK bots so they can pass trough only to be confronted by 10 automated characters per mob.