I have never involved in HRE politics both in EUIV and EU3. But I can't really say that HRE bothers me at all. It is there in the game, I deal with my interests and don't care about what is going on in HRE. Therefore I don't really feel a need to get rid of this feature from the game. I would rather want devs to expand on the mechanism and implement more similiar feature, e.g. Commonwealth shouldn't be played as one huge country but as combination of two nations (or even three when considering Zaporozhian Cossacks) maintained by some nice mechanism.