Honestly, I don't know. I JUST finished Max Heart recently, moving on to Splash Star, and with only Futari wa, Heartcatch, and Suite also under my belt...well, I don't exactly have the right to compare Smile to anything else.
But...this series does give Precure a more "realistic" approach. As others have said, they really in the sense make them look like noobs to the gig compared to those who've quickly adapted. I mean, 7 episodes in, Happy still forgets that she's got super-enhanced jumping ability. I find that the realistics in the heroics (lol rhyming...) is what makes this show enjoyable to me. (I stress the fact that it's what makes the show enjoyable to me...just so it doesn't look like I'm speaking for everyone...'cause I'm...y'know, trying not to.)
......And unfortunately, I know that's not gonna last long...