None of these are icons IMO.
Jay did a good jive, but that was all. His showdance was terrible IIRC. I love Oti but for some reason I didn't enjoy watching Danny Mac. Ashley was just a pro dancer and so didn't have the Strictly factor for me. Layton is highly annoying and another uber-ringer.
How about bringing back Chris Hollins? Or John Barnes doing his salsa? It was the one good dance he had in him, bless him, but it really was good.
Jill Halfpenny may be older now, but she did loads of dance as a child and into adulthood, so I reckon she's in fine fettle still.
I'd like to see Faye's CC again, although of course her partner was Giovanni, so they'd need someone else.
And Zoe Ball's samba from the final. Or ballroom tango. That would also mean bringing back Ian Waite, yay!
And Mark and Karen's AT or their (underrated) samba.
Debbie McGee was a ringer, and I didn't generally enjoy her that much, but her AT was mind-blowing. Again, though, there's the Giovanni issue.