Nexus Blitz Sudden death ABSOLUETLY needs to change

We had just aced the enemy team and were pushing for the end. Attacking their final tower before the nexus, when Sudden Death begins.

We had MORE than enough time to end the game during the ace, but due to sudden death the new nexus is SO MUCH TANKIER that we could hardly get it to 50% before they spawned. All of them full health and freshly bought, with the base right beside them and our nexus wandered the full distance across the map - we lose the game.

From an earned win to a certain loss because our nexus literally walked the entire distance of the map.

The nexus should stop in the middle and wait to duel. Further, the nexus shouldn't be nearly as tanky. Like no where close. I don't even get why it has to be tankier than the normal nexus - this is sudden death, it's supposed to end the game. Not be a an epic long-lasting finally. Most games don't get there, and when they do it's supposed to end fast. Finally, the nexus' should have partial damage taken for towers destroyed. You've lost your entire base? Your nexus starts at half health. We've only lost our outer towers? Ours starts at 90%.

I'm getting really sick of sudden death. Everything else about the game is great. I'm 25/17 overall now, and I'm 1/6 in sudden death - with 4 of those beings games we were very close to winning but the above happened, or the enemy team just had more AD damage to win the sudden death race.