I have to give him a 7 (7.5 if that was an option), which is due to how fantastic the Mattitude V1 gimmick was (though it got cut short due to him wanting to be on Raw with Lita cause he was such a simp
) and because of how well he re-invented himself through the Big Money Matt and Broken Matt gimmicks. Probably one of the most amazing gimmick changes after a huge stretch of being straight up boring. Just to backtrack, he came off that awesome short lived V1 run having really good matches with Chris Benoit, Rey Mysterio, etc and being very entertaining with Shannon Moore and Crash Holly, to heading to Raw and getting beat up by Kane every week, then left the company after finding out Lita, WHO HE ENDED HIS GIMMICK ON SD TO BE WITH, was cheating on him. On top of that, he came back to the WWE after building up quite a buzz...only to shyt the bed in his returning promo. His feud with Edge was red hot,and provided some good matches, but dude looked like a loser throughout and couldn't cut a promo to save his life. Now he was pretty entertaining during his sulking gimmick when he had a broken arm and feuded with Jeff Hardy (and the Wrestlemania match and build were nice), and him and MVP had a pretty fun dynamic teaming with and feuding together, but most of post-Edge/Lita to 2010 Matt Hardy was one of the most unappealing faces ever. His general wrestling skill was also deteriorating. Not only that, but he was moving around the ring like he had Great Khali legs, and started looking very out of shape (I remember him saying he wasn't allowed a lengthy recovery after he tore his abs or something, causing him to look all flabby). I couldn't tell you any good-great matches he's had between ROH up to this point, but Big Money Matt and Broken Matt have provided tons of entertainment until the WWE watered it down and did their corporate variation of it. Dude has been stale ever since. Taking Big Money Matt, Matt V1, and Broken Matt out, Matt Hardy solo wise may legitimately be a step above Tommy Dreamer status. Without those, he's probably a 5-5.5. With those, he's a 7-7.5. Plus, he's obviously part of one of the best tag teams of a defining era. You can't mention Attitude without Matt and Jeff Hardy, so that most definitely gives him a solid rating.
Just to add, if I could re-do anything about his career, he would have never went to Raw, and he would have further cemented himself in the V1 gimmick and became an upper midcard mainstay, but shyt happens.