Oh hell yeah there's no denying, but what sort of makes me hesitant to believe that it could be her is that if the tyrells wanted power they would not do so with Margery at such a fragile positioning. She was still virginal, without his son, and the younger boy was way to young. Sure he could step up to marry but that means cersei as queen regent for some more time, and one of the players they are trying to knock of the board is cersei herself.
but he wasn’t marrying margaery for any reason other than the crown is in hella debt because of littlefinger and the tyrells brought money and food and were in general, pretty loved - with sansa stark’s family ruined she’s an easy piece to move around however they saw fit (winterfell isn’t a huge prize anymore and there was no one to get her a better deal at court what with ned and cat gone), the martells are looking to put someone else on the throne, the tullys are in shambles, the boltons are married off and not rich enough - the tyrells were the only ones in a position to marry into the crown and bring advantages to both the realm and the lannister coffers
no one else could have married joffrey, so margie’s position was really solid, i reckon - still virginal (although like, p sure she’s really not) = prime for marriage, no son bc they weren’t married for an hour before joff’s death, wealthy, highborn, as good as queen anyway, loved by the people, like it only made sense for her to move on to tommen to keep the lannister/baratheon+tyrell alliance. i think it was olenna, for sure. although i believe she was influenced, in part, by littlefinger, right? who came to meet her?
one of the reasons she gives is that with loras in the kingsguard and margaery wed to joffrey they’d have “another recipe for kingslayer stew” so she just kept the crown and moved on to tommen, which, whilst yeah gives cersei more time as regent, also lets those at court become accustomed to margie and gives her time to work tommen around to pretty much whatever she wants.
