The minhag is that the Kallah is not allowed to see the chosson for 7 days before the Chupah. Arguably seeing him right before the Chupah is still problematic and should not be done. This is a halachic minhag and a shailo should definitely be asked before disregarding it.
In addition, there is a non-halachic reason that pretending to be husband and wife before actually being husband and wife is anti-climactic and a little wierd.