For the parliamentary, it is here for a reason. To prevent voting touristic. The delay of several years -- you have to live several years in the other country -- serves exactly that.
But there is no delay, even if I've been in Spain for 10 years I still can't vote for the parliament there.
I know about the local ones but it's not that important IMO.
I could go to the trouble of obtaining Spanish citizenship after 10 years but it is incredibly difficult and long.
I understand the problem of touristic voting but then they should let me vote here after 3 years or so.
Right now I can only vote for the Dutch government which I have nothing to do with in my life (and which is an extreme-right regime since the last election anyway)