Well, we saw Obito's transformation into the Ten-Tails Jinchuriki, and what stands out most, besides the absurd power he gained, is the bizarre appearance he had.

He literally looks like an alien, with almost no human features on his body.

Whereas Madara, after becoming the Ten-tails Jinchuriki, He acquired a much more divine and elegant appearance than Juubito, as if a perfect fusion, but why?

  
Reason 1: Inability to handle the power, As we saw in their fight, there were times when Juubito didn't even remember his own name or could control his own body, Obito, because Obito's mind and will were a total mess, He didn't know what she truly wanted, if he regretted his own decisions or if he wanted to continue the Infinite Tsukuyomi; he remembered Rin and his past many times...Obito was literally losing his mind.

  
Reason 2: Imperfect Juubi, Juubito possessed the Juubi, which had 7.2 of the Bijuu, in addition to the two missing halves of Kurama. Obito had only absorbed a part of the Hashibi; Obito's Juubi, unlike Madara's or Kaguya's, was not the Juubi at It's full power and potencial

  
Reason 3: Rinnegan that wasn't his, The Rinnegan in Obito's eye was actually Madara's Rinnegan; Obito's body wasn't made to possess the Rinnegan, The technique that recreated the Ten-Tails was the Gedo Statue, a Gedo Statue that only the Rinnegan can summon and control, a unique ability of the Rinnegan

Unlike Madara's, who, besides being the true owner of the Rinnegan, could do things that Nagato and Obito couldn't, For example, changing his Dojutsu at will, Madara could freely switch from his Rinnegan to his Eternal Mangekyou Sharingan or to his three-tomoe Sharingan, or he could use his normal eyes.

  
Reason 4: Madara himself. Madara is literally superior to Obito in EVERYTHING, Madara is practically a god in human form; he never had any difficulty controlling the Ten-Tails power, the Juubi, which was stronger than Obito's Juubi.

  
Madara is the original wielder of the Rinnegan, Madara's body was perfectly suited to controlling the Rinnegan and its powers; His body was the perfect vessel for the Ten-Tails, and Madara could use it's power any way he wanted

  
Madara had no doubts about his actions, determinations, or objectives, Madara doesn't cling to the past like Obito does, That's why Madara's body didn't go out of control, or why Madara didn't stop remembering his own name, Madara is Madara.

Reasons why Juubito is so different from Juubidara: