The extra function for CHANMODES=* would not adversly effect EFnet users or any users. There's no reason why it simply cannot be an extension of an the existing function which allows mIRC to recognise CHANMODES=* to begin with.
That being that when mIRC sees CHANMODES=* it will recognise ONLY what modes are included there and no other. On servers that do not support CHANMODES=* and I am sure they have their reasons, then mIRC would behave as it does now.
As for your mention of a dynamic channel central, the thought I am trying to get across is that a channel central is "easily scripted" a term you are known to use from time to time whereas support for CHANMODES=*, where it does not exist, is not scriptable at all as far as I know.
