The fan base of the Super Smash Brothers games have created an image that shows how Bowser has changed in looks and design since his first appearance in Super Smash Brothers Melee up to his latest appearance in the new Super Smash Brothers game. I would recommend you take a look because it is quite interesting how Bowser has changed in appearance between Smash games.
Personally I think Bowser has looked better every game especially given that I don't believe he looks right in Melee but he is looking pretty good in the new game. Though I must say he did look pretty good in Brawl but personally I feel it is better that Bowser looks more like himself from the Mario games and not like Brawls more dark and gritty Bowser and the new game shows him as he really looks.
Source: Nintendo Everything