I don't talk up Greninja as much as I just try to explain him more. Most of the time I have posted long posts about him were because someone was unaware of what Greninja has going for him and just put more emphasis on the bad. People do tend to accentuate the negative after all, so I try to present some of the good to balance it out. I'm fully aware of all the problems Greninja has, I just don't think those problems are enough to make him lower than high-mid.
In a lot of ways, I feel like Greninja plays more like an ACTUAL ninja, using stealth
and misdirection to mislead his opponents, only striking full-force when he sees clear vulnerability.
As opposed to the glorified Ninja Gaiden-esque ninja which is just attack attack attack when it comes to fighting.
Here comes a weird example: ScrewAttack's Death Battle between Zitz (Battletoads) and Leonardo (Ninja Turtles).
Basically, Leo had no way of winning against Zitz in a straight fight due to the vastly superior firepower at Zitz's disposal,
but instead he used real ninja skill to stay safe and frustrate Zitz.