I like the data, yet I can't agree with you unless you count the Wii U in. Yes, you did say that they're playing their game. Never underestimate Nintendo; they may suck today, but you'll be surprised later.
I do feel that this generation we will see the breaking point in budget/profits/success/ power. Games:
are becoming more expensive to produce,
we want even better graphics,
(that's costly)
developers invest more and NEED sales
if games sell bad we may see more closing of studios.
To sum up, I think that this generation games' budgets will finally stop to grow, as it will be impossible to invest that much and still sell it for 60 $ or so.
And Wii U is in that sweet spot where it has some power, but is not a beast. and 300 $ only, with a possibility of hitting 200-250 $, a price unachievable for PS4.