I've seen some paddles (lightweight balsa...the wham paddles that come with the string & ball) that are much lighter than I tend to be with my hand. IMO, there's no substitute for the hand. Nothing like skin on skin. Happily I've got big hands, but that's certainly not a requirement.
It's not so much about what you use.
But in a romantic setting, it can be not so much about the spanking...just a different kind of foreplay. In that case it's more about making things warm and pink than making them sting. Go with softer, faster, repetitive smacks rather than the slow, make-you-count-and-if-you-mess-up-we-start-over kind of smacks. Entirely different kind of thing. The difference between a happy, softly moaning response and a 'oh my god..wait..wait......ok...15' response. Just depends on what you're both in the mood for...and there's lots of levels in between, just like anything sexual - communicate and you'll find the right level for both of you.
If you want to roleplay with it, the schoolgirl thing with the pigtails & skirt works reeeeeaally well for a lot of people (me included). I've had a girl tell me she just can't help but be sassy in that outfit, and sassy is perfect, from this spanker's point of view. If it's a male receiving the spanking, I suppose it wouldn't take much imagination to find similar characters.