Varun is the most promising ? 😲. How ? He has stagnated, not shown growth. Sid, Ranveer and Arjun have shown versatility and growth in a short time. Especially compare Sid and Varun. He like Pari started better than Alia and Sid, but both have overtaken him IMO.
As for dialog, clean your ears. The majority of actors do not enunciate. And most people in RL mumble, swallow words, have an accent and so on. Why should film be different. It would be ridiculous and unrealistic if everyone spoke slowly and clearly on screen.
One of the greatest characters in film is of Vito Corleone in the Godfather. Marlon Brando. Can you understand anything he says ? He mumbles. It is legendary that Brando stuffed his mouth with cotton for the audition and wore a mouthpiece I think to create the character. Ranveer and Arjun have shown nuances in speech for me in the characters they have created. My God, if you cannot hear a difference between Lootera and Ram Leela, have your ears cleaned. 🤔