Same order of magnitude, actually. Dragonfly is about half the mass of MSL, and because it's so easy to hover, it can have a pretty decent scientific payload. A rover with an arm can more easily approach specific rocks and sample them, though. But Titan is a very mysterious world that we can't get a super good look at from orbit (and which we've barely even glimpsed on the surface), so being able to fly around to many sites is going to be very helpful. Titan has some really interesting and varied geography, too, so the pictures are going to be really cool.