"I really do not know. It sounds to me as purely speculative subject. I do not know how RAAL ribbons sound and I am not a big fan of ionic tweeters as I never seen them to work successfully with any other type of transducer.
I have heard them work very well with the Lansche Goa speaker but less successfully with Acapella. I think you should give one a try with your system Romy, although the ribbon you use now is likely to be very good.