So you're saying the ******* of Driftmark is actually loyal to Stannis? And that Stannis finally achieved a political victory through intrigue over the Lannisters (something he's been notoriously unable to do so far)?
On the other hand, Loras really wants revenge for Renly (Loras loved Renly even more than Brienne). He unjustly slew Emmon Cuy and Robar Royce (iirc) over Renly's death and he would have killed Brienne out of hand if Jaime had not intervened. But after talking with Brienne, Loras now doubts who killed Renly... It seems that Jaime and Brienne have persuaded him that Stannis is responsible for Renly's murder... so perhaps Loras stormed Storm's End in hopes of killing Stannis. Did he know that Stannis was now in the north and not at Dragonstone?
Who is doing the planning and thinking for the Tyrells? Lady Olenna? Does Mace actually include her, or are many powerful players in the Tyrell camp actually loyal to her and not Mace? Is Mace really a blustering windbag or is that just a cover? Loras has shown some base cunning, but I doubt he's the brains. Willas and Garlen are more likely to be the brains. Willas is limited in movement because of his injury, but he's the eldest son.
Garlen has gotten himself some real lands and is now a powerful lord in his own right. Renly might have been a poof, but would he really have initiated a relationship with the fourteen year old son of one of the most powerful men in the realm? Perhaps one of the Tyrells, Garlan or Olenna set it up. If they had provided secure locations, then the relationship could easily have blossomed. Renly admitted to scheming to make Margaery Robert's new queen... and I doubt Loras could have done that by himself.
But as Queen, with a firm hold on Tommen, and with the Regent on the outs, Margaery is not just a Tyrell pawn... she is a major player in the Game of Thrones.
What if Loras swings both ways? What if he and Margaery were as close as Jaime and Cersei? Could the moontea have been for their relationship?
Lots of questions, no real answers.