I think the St George's flag should be reclaimed fully from the racist groups just as the Union flag was back in the 90s (remember, for instance, Geri Halliwell's dress had a peace sign drawn on the back to avoid NF associations) But I don't think that has been achieved at the moment, arguably, and while it would be much better if it could be raised with no more issue than the Welsh dragon or saltire, that isn't the current case.
The Union flag being raised would have been very different imo, and caused far less controversy. The associations of that have positive links to fairly recent history too : the Cool Britannia era, then the Jubilees.