Speak for yourself! I love all 649 Pokemon and can't wait to see what new ones they invent. I'm still waiting for a moose, alpaca, goat, possum, platypus, mosquito, barreleye, vampire squid, narwhal, dolphin (seriously, there hasn't been a dolphin yet??). Not to mention new type combos: Dark/Electric, Dark/Psychic, Fire/Water, Steel/Ghost, etc.
And it's not like they don't continue to expand the potential of the old Pokemon. Gen 4 added loads of evolutions for old Pokemon (I.E. Tangela -> Tangrowth, Magenton -> Magnezone, Electabuzz -> Electivire, etc), and each sequel adds new abilities/moves to spice them up.