The only thing that changes is the respawn times go down for the losing team. easy way to avoid that? after killing them...base quick and come back out...problem solved. Also dont get over zealous and try 5 capping just cuz you have a 400 point lead...that just leads to dying, you being dead for 45 seconds and giving them an opening to cap nodes. If you are smart and just defend your nodes and neutralize theirs you will win just as easily without losing your lead.

If the enemy Nexus gets to 100 points, champion deaths no longer reduce the Nexus points. So, if my team is ahead by 400 points and the enemy team gets to less than 100, the effectiveness of killing the enemy players will be significantly reduced.

And yes the respawn timer changes for the winning and losing teams. The difference also depends on how far behind the losing team is.

To be clear, these systems aren't actually intended to be "catch-up" mechanics, and if they've fallen too far on that side of things then we need to ratchet them back. What they are intended to do is counter-balance some of the design implications of making a very small sized map. When making Dominion we quickly found that attritional style gameplay, the need to go back to base and the travel time associated with reaching a point again, was a very important factor to allowing back and forth gameplay from both teams. You see this on Summoner's Rift when you look at how champions move and react to one another as people die and fights are resolved. At the same time we also found that a small map was needed to have the battles be engaging and to get the proper mixture of allowing for back caps while also giving people time to respond.

By shrinking the map size we reduced the attritional gameplay that's core to the game balance, and so we needed to think of another way to create that sense of "travel time" that allows for a good back and forth. Adjusting the respawn timers seemed the best way to create this type of gameplay. We considered basing the adjustments off of the number of points a team controlled at any given time, but we scrapped that idea as it then felt punishing to ever get more than 3 points and led to stale gameplay. Basing it off of the aggregate score was less penalizing tactically and overall a better experience.

As an analogy to SR, think of it like the respawn adjustments are simulating how far into enemy territory your 5-man group is running. The closer to the enemy base you are the more likely you are to win the game, but the more punishing dying can be in terms of letting the opposing team rebound.

This is a main area of our design focus right now to tune this properly as I agree it's a very sensitive subject, and the more feedback that you guys can give us over the coming patches will help us guide it in the right way. Definitely expect continual changes on this topic.

Did you consider disabling the bonus/penality while the team that's behind in Nexus health is ahead in point controlled?
It's very bad when one team has 3-5 points yet much shorter respawn times, it causes the exact opposite of what the system is supposed to create.