It's an interesting thing trying to compare Robbie to anyone.
Personally, I think the best "fit" to any player today is James Hird. Similar build, Flower was quicker in his prime, opponents just couldn't touch him. Robbie wasn't as "inside" as Hird is now, but the game has changed a lot.
He played in an era when players tended to be "one position". But he played CHF for Vic against WA one year. Beat Glendinning pointless, and Ross was a fantastic player.
Robbie was a once in a lifetime player for me. He was 100% skill. He was the reason that the Dippers existed. You couldn't beat him, you had to neutralise him.
He's the reason I hate thugs on the field. For all we can admire the bravery of Archer, the determination of Kirk, we go to the footy to see the skill of Flower.
Make no mistake. He was, in his own way, the equal of any footballer I've seen since 1960. He just did things nobody else did. And he did it regularly.