They can't repeat championship, that was a one time trophy due to too many injuries on opponents. Next year there won't be this much injuries.
We never know, now that Bucks had already won a championship, we will see a more confident Milwaukee Bucks next season, also, expect that Giannis will improve as he is still young, they will try to develop him into an all-around player and more consistent with his FT shooting. The first five should remain intact, they can add some players to improve the teams' offense, particularly the 2nd unit as they might face a tougher challenge next season.