no, i don't think they will. think about it: if they had been so concerned about the tieing-in of similar pokemon, then they would've made pinsir evolve to balance out scyther's evolution, scizor. however, if you ponder the stats of both scizor and scyther, they don't change much, just the type of it changes from bug/flying to bug/steel. perhaps they did this because there seemed to be a necessity for a bug/steel pokemon that looked so freaking cool and learned great moves. same goes for an electric/dark (in assumption) pokemon, which would explain "electabull". if the creators at pokemon were so concerned with fulfilling the nature of the pokemon evolution chain quite the way us fans expect them to, then there would be no need to continue making further generations. just my opinion.