New ThunderCats!!

Just a little thought if I were to do my own version of ThunderCats, I'd look to how lions, tiger, leopards and jaguars (and snow leopards, but to my knowledge we haven't had a snow leopard on screen in the franchise) are all members of the Panthera genus and re-imagine the clans the 2011 series introduced with the lions, tigers, leopards, jaguars and snow leopards all being cadet branches of the House of Panthera and that all of the high-ranking members of Thunderan society would be members of those branches with the lower ranking members being non-Panthera cats.

Thinking of it in the terms of a season for a tv series, characters like Cheetara, WilyKat and WilyKit, Lynx-O and Pumyra would not actually become ThunderCats until the final episode of the first season at which point a reform would be passed allowing for non-Panthera members of Thunderan society to rise higher than they would have been able to prior and thus, serve as ThunderCats. Grune, re-imagined as morally grey rather than evil, would have not become a ThunderCat due to the fact that while he would have his good and bad qualities, the latter would include being unable to follow orders he disagrees (meaning he'd try to force things to be done his way), his inability to work as a part of a time due to being more focused on winning glory for himself, him being easily angered, having no problem flirting with married women with their spouses in front of them, treating his own significant other poorly and having a feeling of entitlement to a higher rank because of his service. Him being passed over for being a ThunderCat would ultimately be his contributor in defecting from Thundera.

Panthro would be Grune's superior, hopeful that with his guidance he could free Grune of his less admirable qualities, thinking he could be quite good at a higher rank, even as a ThunderCat, if it were not for his flaws.

As for Tygra and Cheetara's romance, it would be like a romance between upper class and lower class citizens.