To add my reasoning here:
I believe no tick limit is better for two reasons:
It ensures there will be a real winner at the end, who has had to kill or subject all other alliances to gain all 10 relics. It ensures an absolute win. I believe this is what a Champions Era should be all about.
I believe having a tick limit gives off the wrong message. When there is no tick limit, it is clear to everyone that delaying when the era is already done has no use. If there is a tick limit, even if that limit is 4k ticks, then there will be teams that will see the benefits of stalling at some point. Whether that stalling would start at tick 3.5k, 3k, or even earlier, I do not know. I do know that it would be a valid strategy, especially if there are teams that simply build the biggest coalition that can have them feed all the crystals and relics to them for score. I think that because of this, it is far more likely that the era will go to the tick limit, regardless of how high you make that limit. A no tick limit era might actually take less long than a tick limit era does, and the era with a tick limit would definitely be far more monotone and boring at the end as it would simply be a stalling game.
Because this is the last hurray, the final Champions Era, and because I want it to be a real Champions Era and because I prefer a dynamic, active, skillful era over an era where stalling and sitting is rewarded, I would much rather see the tick limit completely removed for this special era.