I don't think that hurling would benefit from moving to a straight knock out similar to the football, nor do I think that the championship should be reduced to 16 teams... yet.
The hurling calendar should be split in two. League until August, and championship after that. I think the league should be played off before we start championship. If county players are made available, great. If not play them away. However if leagues are played in advance of championship - it can avoid the hold up of league play offs later in the year.
I think the Dublin championship should be revamped (to similar to the football championship a few years ago) to a back door system. Each team guaranteed 3 games minimum. To reach the final the direct route you play 4 games, through the backdoor you play 5 games. Similar to how it is now. To be relegated you'd need to lose 4 games on the bounce. Once a team win ones game, they avoid the drop.
16 teams, open draw for the first round.
The 8 winners play each other in round 2 to progress to the quarter finals of the championship, and be seeded teams to play the 4 teams that come through the back door.
The 8 losers play each other in the back door round 2 to get back into the championship. The four winners of this section play the 4 losers of round 2 above, with the four winners progressing to play in the quarter finals.
The 4 teams that lose here progress to the relegation semi final, and then relegation final. With one team down and one team up.
I think this could benefit the championship - can add a bit of bite to the championship. As there could be a few teams playing for nothing when the championship recommences later in the year.