Well, it was more than just age catching up to him--he did spend three months on vacation after being shot in the chest by a sniper rifle before falling from a bridge. Had his body been recovered and survival confirmed, his recovery would have included physical therapy and training, whereby he would have kept in better shape.
If the movie seemed a bit meta, keep in mind that this was released amid the 50th anniversary of the Bond franchise--the film's little nods and self-commentary were a part of that sort of celebration of the character and his world.
I didn't note a whole lot of technical jargon, which is good for a film centering around such a simple-but-effective character. Q wouldn't waste time giving Bond technical details, nor would Bond be the sort to entertain them--he's sharp enough to understand, but would much prefer to get to the point. He can figure out the rest on his own.
And the Bond girl only gets short-changed only if you assume Moneypenny or that other chick were the Bond girls. I feel that this time around, it was Dench's M that was the real Bond girl.
Regarding Bond's survival, I feel like that was a story along with a couple others (such as when he got onto that woman's yacht), that were cut from the film--keep in mind that the film was two and half hours. And really, it doesn't matter how Bond survived, its one of those things that the viewer can probably draw their own conclusions.