Another answer already mentioned adding more liquid, which was my first thought, so I'll just mention a few other possibilities.
Depending on the amount of batter you have or need from the recipe, you might find it easier to add a little less flour rather than more water (like maybe a tbs less to start with and recalculate after trying it?). Aside from having physically less batter, this would also make your pancake taste a bit richer and less bread-like, effectively leaving the mix with a higher proportion of eggs and oil and even salt, instead of diluting the batter with milk or water and the extra flour.
You might also try using just a little less baking powder, if the height is a moderate problem - it should make the pancake a touch denser and less fluffy, which may actually be useful depending on what you were looking for out of a pancake.
Also, you mentioned your objection to spreading the batter out for a thinner pancake is because it's messy... if you don't have any other objection than that, and especially if you like the flavor and texture (which meddling with the batter will alter), you might try spreading the batter out with the back of a ladle dhosa-style - that is, as soon as you pour the batter, use the ladle to make a tight spiral out from the middle, which smoothly and evenly moves the batter outwards. You can actually make the pancake as thin or thick as you like with practice, dhosa are usually fairly thin and crisp but the basic technique is adaptable by picking which hight you're holding the ladle at. The results are fairly aesthetic, either a smooth circular pattern or, if the pancake was a bit rawer on top, it might even smooth out the spiraling, and it really isn't difficult - and you don't have to wash an extra tool like using a crepe spreader would require.
Alternatively, if you have a steady hand, you can pour the batter in a ring or spiral in the first place. If you dump the ladleful of batter in the very center, it can kinda pile on top of itself and only spread slowly from the edges - and often start setting before it has time to finish spreading. If you spiral it out as you're pouring, it spreads from every edge both inwards and outwards until it meets the next layer (or finished setting), and will settle at a lower overall height. You might have some gaps or thicker puddles while you figure out the technique of how quickly to pour and how much space to leave between (and you can patch a bit with more batter or a swipe of the ladle to spread and thin), but it can work with patience and hand-eye coordination.
