There's a tendency in Hollywood to generally play the card of English = bad. If you don't believe me, watch Braveheart, or The Patriot, Titanic (noting that the only lifeboat that went back to look for people had a Welshman in charge) or even Frozen (the Duke Of Weselton). But here it's justified, unquestionably so: if you don't know the history of King Edward I, go and watch Simon Schama or do some reading. The stuff he did that isn't covered in Braveheart - the stuff he did to people other than the Scots, notably the Irish and the Jews - was almost unspeakably bad at times, making Machiavelli look like a benevolent softie. The parallels to (among other people) Hitler are actually justified and at times uncanny, and I say that knowing full well about the Holocaust. This was one evil man.
So to tell the story, all you need to really do is to accurately portray Edward Longshanks, then show the battles of Stirling Bridge, Falkirk and Bannockburn. While the focus of the film is Wallace himself - thereby reducing the focus on Andrew Moray and particularly Robert the Bruce - the story is told quite fairly and clearly, Wallace's shortcomings exposed every bit as much as his inspirational leadership. And inspirational it was: to this day - and even prior to the release of Braveheart in 1995 - flowers and memorials are placed in London at the site of his execution. The Scots have a forever-hero here, and will always be able to look to this man, and others like him, when they think in terms of both political independence and, more importantly to my eyes (as someone by birth half-English and half-Scottish), cultural heritage.
Plus of course it's a darn fine film to watch, over and over.