The years are already stated on pets so I'm not sure why adding it again would help. Also, year can sometimes not matter at all. The RBM, bunnies and wolf PPS are from 2009. Yet they're all worth more than 2008 advents. Zebras and Malk dragons would be tricky since they're available most years. Store pets are all worth vastly different amount even if the year is the same etc.
Why does 14 rarities sound like too many? We have over 8 thousand pets on CS and 7 rarity markers. Meaning if you happened to have a thousand rares in your collection, it's like not having any rarity markers at all for those thousand pets.
What if we subtracted OMGSC and replaced is with a new store pet rarity, because c'mon people do we really need OMGSC when we already have very common? Isn't that enough? Addressing another issue on that topic, why are there more commons than OMG so commons? Aren't OMG so commons meant to be more recurrent than commons or very commons? I don't really get the idea of OMGSC if they aren't frequently seen and are less redundant than commons.
Rarity is based on how many pets per person. So, let's make up some numbers here for a minute, OMSC is everyone has at least two of this pet and Common is 1 pet for every three people. So until the pet hits that threshold, that's what it's rarity is. Of course there's more commons because it's easier to hit "1 pet for every three people" than there is to hit the other number.
Also, should we have an 'uncommons list'? This list WILL NOT include rares or commons etc. I have noticed its is extremely hard to obtain a list pet of any kind (unless you are lucky). I find this a bit irritating, and some people demand a ridiculous overpay for their Advent Teir 7 pet, but I guess that is the whole fun of trading on CS. Anyway, there are some uncommons that I have noticed a lot of people are rather attached too and/or have a really nice design and everybody wants one.That dog litter from 2014...oh never mind It would be nice to classify all these pets.
Would you really want a list of "here's the uncommons that are in the highest demand"? Not rare, but here's the pets most likely to be asked for in a trade? I think that would turn into the rares list really quickly where people use it as a bible: "my pet is totally worth this much and you're cheating me! You owe me 7 more uncommons for mine!"
Actually now that i think about it that might actually help the problem of, we have over a thousand pets per rarity now. If nothing changes, we may have to start drawing up lists for each rarity marker since that's the whole point of the rares list. (These pets are worth way more than other Very Rares)