But there have been times when I think it's been too slow. Because let's be honest, the reason we watch Gotham is because we want to see Batman. Bruce Wayne has been in the show since the beginning--the series began with the murder of his parents. But since he was only eleven or twelve when it happened, he wasn't exactly going to be Batman right away. In most portrayals, we start with Bruce's parents' murder, and then skip ahead a decade or so, to after Bruce has traveled the world, training with world-class experts to become the best at absolutely everything: martial arts, investigation, driving, inventing, even developing esoteric skills such as meditation.
But in Gotham, we watch him grow up. Rather than being trained by experts around the world, his principal teacher is Alfred--though admittedly, this version of Alfred is former SAS (British special forces), so he's taught Bruce how to fight. Bruce has also been hanging out with the young thief Selina Kyle, the future catwoman, and even stayed with her for a while so he could learn about thieving. Exactly how long is never stated--it was several episodes, which could have been anywhere from a few days to a few months. It was at least long enough to learn to pick locks, which he seems to be fairly proficient at these days. Finally, one of Ra's al Ghul's lieutenants, the Sensei (who's actually al Ghul's father in the comics, though that's never stated here) briefly kidnapped Bruce, primarily to brainwash him, though there was also some martial arts training involved.
Anyway, Gotham's always been interesting, but the end of Season 3 threw away the slow part. A lot happened, with Jim Gordon, Selina Kyle, Ra's al Ghul, but the most important development was with Bruce Wayne.
Bruce has finally decided to become Batman. Well, not Batman specifically, but a vigilante, fighting criminals. On the one hand, this seems like it's too soon for Bruce to become Batman. On the other hand, we've been waiting three years for this to happen, so lots of people (like, the whole Internet) is excited to see this.
The rumor is that the showrunners didn't think that Gotham would be renewed, and wanted to end the show with everyone moving in the right direction for their ultimate destinies. It looks like they did too good of a job, and everything's now moving way more quickly than before. It will be interesting to see if they can keep up the momentum.
That doesn't change the fact that Bruce is not ready yet. He knows how to fight, obviously, and he's learned some of the sneaking and thieving skills he needs, but he's clearly not the polymath that Batman is, so it'll be interesting to see how things develop.
To some degree, I expect the next season to have a Batman Begins or Batman Year One vibe, as he slowly develops the arsenal of gadgets and techniques that Batman uses. But in both those stories, Bruce Wayne already had the skills. He just needed to work out the method to use. Here, I think Bruce also needs to learn what he needs to learn. This will happen as he runs into challenges in his vigilantism he can't overcome with his current skillset. When he does run into those, he needs to figure out how to get the skills he needs.
There are several ways to go about this.
Obviously, Alfred will continue to teach him how to fight. He also may teach him more Batman skills, such as fancy driving, throwing weapons, rock/building climbing, etc.
There are also other experts in Gotham who could help train Bruce. The first time his vigilantism requires Bruce to solve a crime, not just interrupt one, he could turn to his friends in the GCPD, especially Lucius Fox, to help him not only solve the crime, but to learn how crimes are solved. In the movies, Lucius is also portrayed as the source of Batman's gadgets (more so in Batman Begins than the comics, where most of Batman's gadgets are invented by Bruce himself). Here I expect him to not only provide gadgets, but to teach Bruce about science and inventing. Jim Gordon may also help in developing some of the investigation skills, though unlike Lucius, in most continuities he doesn't know Batman's identity.
Selina Kyle is still around, though her current relationship with Bruce is frosty. Still, when it comes to sneaking and breaking into places, there may be more teaching that she can provide.
Then there's Ra's al Ghul, who showed up in the season finale as the true force behind the Court of Owls. Ra's wants to make Bruce Wayne into his heir to lead the League of Assassins, and the fact that Bruce was able to overcome the League's brainwashing just makes Ra's more intrigued. Bruce doesn't want to be al Ghul's heir, of course, but that doesn't change the fact that Ra's is willing and eager to teach Bruce all sorts of the ninja-like skills Batman needs--from sneaking around, to impossible feats of agility, to martial arts mastery,
Finally, it's not unusual for Bruce and Alfred to leave Gotham for months at a time for vacations. It wouldn't be out of line for such vacations to become cover for some intensive training of one type or another with an expert that Bruce learns about, or Alfred knows through his contacts. It's possible that some of those trips already involved more than visiting a ski lodge.
I'm not expecting a full-fledged Batman next season. Maybe if they think the show's going to be canceled again, they'll give it to us in the series/season finale. Otherwise, what I expect to see is Bruce slowly learning what he needs to know to be Batman, developing the tools and techniques and skills he needs, and possibly learning that he needs something more. Not just more training, but an identity, an icon, to make him something more than a viglante: a symbol.