Power hitting is a must.
I'd take Kohli above Babar any day of the week, just because he's a much better player with more range in almost every aspect.
T20 is about moving out of your comfort zone, only then will you develop new shots and understand how to play the game.
It's quite an interesting thing, but those who follow Kohli will know that it's only in recent times that he's developed that heck of a leg-side flick for 6. Before he used to dab it down to the ground, but if you see how he plays now, he is able to move in the line of the ball, and use his wrists to slap the ball over the boundary line. It's such an amazing shot, showcases his class.
Let's look at the strokes Babar uses for T20 cricket:
1. Cover/On/Straight drive along the ground - good strokes when the field is open, but not good for the powerplay when aerial strokes are needed.
2. Front-foot pull along the ground - again, it's a stroke along the ground so if it's for rotating strike, that's fine but it won't get him much when the powerplay is over.
3. Cut shot/sweep shots along the ground - yet again another set of strokes played along the ground, so for strike rotation and occasional boundary hitting it's fine, but not good enough for hard hitting.
4. The shot where he nudges the ball past the keeper - this is perhaps a very useful shot when done correctly, so I'll give him credit for it.
5. The harmless slog that he sometimes plays over long-on and usually gets caught. As suggested, it doesn't yield him many boundaries either.
6. The leg-side flick along the ground - good for running singles and doubles, will rarely fetch a boundary.
What does this shot selection explain? These are the 2010s must-have for ODI cricket, and it's true that they work but outside of ODI cricket, these shots don't work. It's quite surprising how he's managed to keep his SR at about 130 with such a limited shot selection, but the bottom line is that these shots aren't enough.
The facts are in front of us, these shots are just not good enough for T20s at this level. If Babar wants to improve his game, he needs to improve his shot selection and what better do to than sit down and watch how Kohli plays.
A few shots Kohli plays which Babar can replicate are:
1. Back foot pull - it is essential in the modern day and age, without it you won't do well against short-pitched bowling.
2. Most of the drives I mentioned, Kohli has the timing to play them in the air, and miraculously for six. This is where the true muscles and timing are required, and these shots are essential.
3. Hitting straight down the ground - this is a zone Kohli uses very well, and it's a good zone given that usually teams keep one player down at long-on/long-off.
4. Slog-sweep - he doesn't play it often but he can play if the need arises. Babar should learn how to play this stroke because he barely uses the leg-side against spinners.
5. The aerial flick - it might be a Kohli trademark that goes straight for six, but even if Babar can get it for four, it will be a good addition to his strokeplaying.
6. Slogging on the leg-side - Babar usually slogs on the off-side and because he's very good at strokes on that side, teams have protection there. He should also be able to slog the ball on the leg-side.
What Babar does when slogging is that he just tries to make contact. He needs to learn how to time the ball in that manner, and improve his power hitting. His bat lift is too low to be able to get the required distance, which is why we usually see him get caught right at the boundary. If he applied more power, those shots could easily be sixes. Secondly, he needs to be mobile and move around in the crease. Slogging doesn't mean that you stop moving your feet, you still need to get yourself in a good position, and when playing these shots, you need to make sure the bat rises up in a diagonal line, not that it whips across horizontally because that's how you play along the ground.
Basically, those are the things he needs to improve.