The point was to confuse the enemy because of all of the Potters, if there had been no Potters then it is likely that the enemy would have simply attacked everyone equally, instead of chasing after whichever Potter they thought was the "real" one.
Mundungus gave them the idea to have seven Potters via Polyjuice Potion through the manipulation of Snape because Snape knew that he would have to tell Voldemort the exact time that Harry would be taken away from the house. Had there not been seven Potters..., a fact that the Death Eater's were surprised about:
"...They didn't know there would be seven Harrys, that confused them the moment we appeared..."
...then the enemy would not have been confused and the events might not have been as fortuitous as they were.
Remember too, Dumbledore told Snape to manipulate Mundungus into giving the idea as his own for seven Potter's specifically to ensure Harry's safety:
"...you must plant the idea of decoys; that, I think, ought to ensure Harry's safety. Try Confunding Mundungus Fletcher."
Now Snape was head to head with Mundungus in an unfamiliar
tavern, Mundungus’s face looking curiously blank, Snape frowning
“You will suggest to the Order of the Phoenix,” Snape murmured,
“that they use decoys. Polyjuice Potion. Identical Potters.
It’s the only thing that might work. You will forget that I have
suggested this. You will present it as your own idea. You understand?”
Edit: If you meant that they still should have had seven Harrys, only that Harry not be one of them that ends up even worse for protecting Harry. The whole point was to protect Harry and since everyone else there could have been killed by any random Death Eater with impunity, disguising him as an "ordinary" person would not have helped. Harry was the only one that the Death Eaters were given specific instructions not to kill (in order to leave him for Voldemort). It would have put him in more danger if he was disguised as someone else, as he would have been one of the "expendable" (in the eyes of the DEs) members of the Order.
If anything the best plan of action may have been to disguise everyone as Harry, at least that way there would be confusion, and the Death Eaters would be hesitant to kill any of the Order rather than just the Harry impostors. However again, if that was the case they likely would have provided equal (or near to equal) coverage of everyone, rather than attacking the pair with the most experienced Auror's first (something that the Order members specifically counted on).