that maybe not suck good idea, but ...
1st idea:
the possibility of replace the handler by a script, like a event
on *:irclink:<server/network>:<channel/nick>:<etc>
2nd idea:
when click in a irc:// link, detect if the server in the link is part of a network you are already connected to, and warn "you are already connected to this network / you want open a new connection / you want join this channel using your active server (same network) / you want join this channel in this server (diferent network)"
this can be done by script with the 1st idea, however, the irc:// handler of mirc is kinda confusing e not very practical, especially to ppl who connect to many diferent networks at once, and dont have experience with irc
