Delta
I’ve always been a strong opponent of delta leaderboards. They suffer from 3 major issues:
- They produce too many ties.
- They basically rugpull people who invested in high XP/Kinship Gotchis
- If you didn’t invest in it, but obtained high XP/Kinship through work and dedication, your past contributions are devalued.
Kinship
There is no question that the Kinship leaderboard is broken, but it is the only play to earn leaderboard we have (XP is more of a “show up” to earn thing). So instead of decreasing its value even further, we should try to fix it.
Kinship was already the looser of RF S2. A quick reminder, here is how much RF rewards changed from S1 to S2:
BRS : 122% of S1
Veteran Kinship : 71% of S1
Veteran XP : 142% of S1
Kinship rewards went down by almost 30%, while all other reward categories went up!
The Rookie Kinship leaderboard was also one of the best examples, why a delta Kinship leaderboard would not fix things. From rank #19 to rank #228, Gotchis never missed a pet. So we had 209 ties for the majority of the top spots (and that was in the end…in the beginning of RF S2 there were over 300 ties). That amounted to 25% of the GHST rewards of the entire rookie leaderboard that was NOT determined by anything related to kinship (like for example time-shift), but instead by XP. And that is ONLY considering this one tie between the 209 Gotchis that never missed a pet and never drank a potion. Not even considering all the other ties down the leaderboard.
How come? Petting bots can still fail. Mine failed 3 times so far and I cought it because I still check manually. And besides, there are a lot of scalping bots on the baazaar. They have been scalping fat finger mistakes and good deals for months, so they get high BRS items and Gotchis for MUCH lower prices than anyone else. Does that mean there is no point in the BRS leaderboard either?
Just because people use bots, doesn’t mean the leaderboard is useless. Especially because there are already services out there, for everyone who wants to use a petting bot, for simply staking 99 GHST. There are no such offers for BRS scalping bots (yet) 
And lets not forget that some people spent some serious cash on Potions. Lets remember 4 (formerly known as BurgerKing) who spent 13k GHST on Potions in a single day. And that was after S1. I mean it was always doubtful that they would make that kind of money back, but rugpulling the guy (or girl) after just 1 season seems cruel. Besides they are not the only one who invested in Kinship.
Right about now I expect people to reply with something along the lines of “Well, we can’t just make our decisions depending on whatever some chads aped into”. But that is exactly what people use as argument why BRS deserves such high rewards. “If you don’t give BRS the big rewards, it’ll crash the baazaar economy. Bad for Gotchi ecosystem, yada yada”. So what’s true for one reward category / investment should be true for another one as well.
Proposed solution to the Kinship issue
I still believe that the solution to the Kinship leaderboard issue would be to use the “binomial proportion confidence interval” (what we coined Dependability) instead and time-shift as a tie breaker.
We can modify the dependability formula to include kinship gains from potions. This way, we wouldn’t rug pull any potion investors / buyers / users, and at the same time give newly summoned Gotchis the best chance at placement.
During RF S2, the top petted H2 Gotchis made it into the top 800 Dependability on snapshot 1, top 600 on snapshot 2, and top 400 on the last snapshot. There would have been no reason for a separate rookie Kinship leaderboard if we had used Dependability instead. Furthermore, now that H2 are no longer rookies, they would get rekt by all the H1 Gotchis in a traditional overall kinship leaderboard. But if we use dependability instead, we maintain the veteran lead (if they didn’t miss many pets), while also ensuring a good placement for the top H2 petted Gotchis.
And like I said, with a small modification to include boosts from potions, dependability would not rug pull potion investors either. So it really is the best solution in my opinion. Including potion boosts would also ensure that my Gotchi is no longer #1 in Dependability, which makes my proposal sound a whole lot less self serving haha 
That said, even with dependability, we would still end up with some ties. Instead of once again crosscontaminating leaderboards by leaving XP as the tie-breaker, we should use time-shift as the tie-breaker. I have been arguing this since the very beginning and as the poll shows, it had overwhelming community support.
Time-shift is actually related to kinship, which XP (or BRS) is not. Time-shift would also benefit people with less Gotchis. What do people with many Gotchis do? They sync up their pets, so they can save gas using the pet-all functionality. However, that causes quite a large time-shift for all the Gotchis that were summoned first, as syncing means you essentially have to wait until all your Gotchis can be pet. People with just 1 Gotchi never had the need to wait with their pets to sync up petting. Also important, time-shift is not unfair to large investors, since anyone could choose to simply pet all their Gotchis individually or group them in smaller groups, resulting in slightly higher gas cost but less time-shift from waiting for sync.
XP
The XP and rookie XP leaderboards also suffer from ties, but there it’s not nearly as bad as for (rookie) kinship. Did you know that if you participated in every XP event since Haunt 1, voted on every proposal since Haunt 1, were an aambasador since day 1 and did anything else that gave out XP, you’d reached between 600 and 700 XP, while 500 XP was given out for voting twice on Aaragon?
In my opinion, being less stingy with giving out XP for things would be a better solution than a delta leaderboard. As a community we do want to keep rewarding people who got in early (to show that Gotchis are a good long term investment), but not to the point where they could be almost absent for 9 months and still keep up with a user with 100% engagement. That is ridiculous.
[EDIT:]
Thanks to @kenymccornick for the correction that it was 500 XP for aaragon instead of the 800 that I had thought.