I only have issue with Pokemon like Blaziken and Lucario getting these Megalutions, because in my eyes they were fine as they were. Now (If I want to battle competitively), I'm going to be forced to use these new more powerful formes, and I don't like them as much as the originals. Absol and Mawile actually look good, but that's because they look like proper evolutions.
Every time something like this happens, a few people get on their high horse and shake their head disapprovingly at the people who don't like the change. Seriously? People will have different opinions. I don't dislike this because it's 'new', I don't like it because it feels unnecessary, and is pretty cheap as far as 'innovation' goes. What exactly will this bring to the table? Pokemon now go into God Mode and kill each other faster. I don't understand how that will make battles more interesting. The whole concept doesn't appeal to me, either. Half of the fun of Pokemon is seeing your guys evolve and become more powerful. Now, some Pokemon (like Absol and Mawile) don't properly evolve. They get temporary power-ups, and I'm sorry - that just isn't as cool.