Mega evolutions are the perfect balancing tool, I don't get what people are mad about. There was already a massive power creep in gen 5, leaving many older pokes in the dust. With mega evos, you can get pokes who can't evolve any more a new lease on life. They're limited, as in once per battle, so they won't overrun the meta. IT also means that eventually, they could potentially add more than one mega evo to a pokemon. For instance if they do keep making stronger and stronger pokes, maybe they just give a different mega evo to a pokemon, just by giving a different stone. So we could have mega lucario fighting forme, mega lucario steel forme, etc.
Yeah, but giving mega evolutions to pokemon that are already really powerful only worsens the power creep problem.
Also, it will overrun/over-centralize the metagame, because all you would really need to do is "mega-evolve" and then sweep with something like Mega Lucario; this will result in an increased use of moves like Knock Off, Thief, and Trick, because everybody will be busy trying to stop each other from mega-evolving.
I know that some of the people here play or used to play some kind of TCG. I used to play Yu-Gi-Oh!, and this is exactly what happened whenever a powerful new group of cards was introduced. They would announce them in the Japanese shonen jump, and then everybody would obsess over them until they got here, and within a week or two of release (if the card(s) really were strong) everybody would be playing with the powerful new card(s), and everybody who wasn't was playing decks that tried to thwart the powerful new card(s).
Competitive pokemon is essentially just a TCG with a deck size of six "cards" and very infrequent releases of new "cards". If pokemon like Mega Lucario become popular, you can be sure that everybody who isn't using them will be trying to make sure that they never mega-evolve to begin with, and thus the metagame will become over-centralized.
As for new evolutions, not all pokemon (who don't already have three) need more of them. Ditto doesn't, Smeargle doesn't, and there are many others that do not need an evolution from a thematic standpoint. Lapras doesn't really have anywhere else to go, in terms of concept. What would you do, give it more horns? Give it wings? It's already big enough and "developed-looking" enough that giving it another evolution doesn't make sense (Lapras could use a few more point in some of its base stats, but that's another topic). Having separate mega evolutions that are like new "formes" doesn't make sense either, because things that could use split evolutions would be better off with a split evolution, since it would be permanent.
Lucario is the
absolute last pokemon that needs anything else done to it in terms of more evolutions or forms.
I hate to break it to ya bud but this is a permanent addition to the Pokemon series. There is no escaping it, even if you do skip X and Y.
By skip it, I basically meant I would just quit playing. I have other hobbies that I could do as well, and I didn't buy any of the generation five games for the same reasons.
Battling is only a small portion of what Pokémon truly is.
But the problem is that the "battling side" is growing larger and larger, while the "story side" is staying the same (in terms of the relative amount of the game that each "side" takes up).
The other problem is that the story is still somewhat lacking in terms of challenge for older or more discerning players. It's gotten better in the more recent generations, but the single player portions still feel kind of like busywork to do until I get to the endgame stuff where I have access to every item, pokemon, and TM and can just sit back and breed strong pokemon for battle frontier stuff and online battles.
Also, it wouldn't be hard to make the selection of pokemon synergize better with both the battling and the story parts of the game. The single-player portion needs weak pokemon near the beginning of the game, and yet competitive play (or even just "serious" battling with human opponents) tends to exclude pokemon without a certain base stat total, unless they have a special niche. The solution is to reduce the gap in base stat totals, so that the difference between the lowest and the highest is about 175-200 instead of the 300 or so it is now.
That way, there would still be a gradient of pokemon strengths available for the single-player mode, but many more pokemon would be viable in the competitive scene, and Smogon wouldn't have to make up as many tiers to house them all, because battling would be mostly up to player skill instead of being mostly up to the base stats of the pokemon used (basically, imagine if there were only NFE, UU, OU and Uber - there would be far more pokemon in the middle two tiers, and pokemon in BL would ideally be brought into OU or UU).
Mega evolutions for pokemon that are already pretty strong don't make sense, and the pokemon that could use a mega evolution would be much better off with either a permanent linear evolution (such as Mawile evolving permanently into another pokemon) or a horizontal/split evolution (like Kirlia > Gardevoir/Gallade)