4. Robin Raises The Stakes
Not to say that putting teenagers in danger is ever a particularly good thing, but the silver lining of this where the Batman character is concerned, is that having a Robin in battle with him only further serves to increase the stakes on offer.
For decades, it's oft been questioned as to why a fully-grown adult vigilante would look to endanger impressionable youngsters by inserting them into life-threatening situations. While there is obvious merit to that question, the simple fact of the matter is that comic books logic means young heroes and villains are just as pivotal a part of the cape 'n' tights brigade as any more senior figures.
But by having Robin - or any of the other younger Bat family heroes - suited up and at Batman's side, narratively speaking that only amps up the stakes for the Caped Crusader. Not only does he have to be at the top of his game to protect himself and to overcome the particular pickle he finds himself in, but this adds another layer to Batman in that it's not just his own life that's on the line during these missions.
To highlight how much further jeopardy a Robin can bring to to the table, we need look no further than A Death in the Family - the 1986 story where Jason Todd was brutally murdered by The Joker. As a reader, amplified stakes make for a more engaging, compelling story.