Delhi's quartet of Indian batsmen - Dhawan, Shaw, Iyer, Pant - is too strong for batting to be an issue. Bowling wise the south african duo is a big plus along with Axar and Ashwin. Only 5th Indian bowler is an issue. Stoinis is in good form and regardless he is the 6th bowling option so he will not be dropped. I think Pointing is backing Hetmyer to come good, they will send him up for another match and that might decide his fate.
Bangalore, I just don't rate their team. Who is their gun bowler other than Chahal? Every other team has one go to pace bowler (bar Chennai also perhaps) and the fact RCB has to waste an overseas slot on Udana says it all. I think their only shot of making play offs is Zampa coming good in combination with Finch hitting top form alongside AB/Kohli. Even Kohli I think needs to reinvent himself as a T20 player, he seems a bit lost in terms of his approach as of now IMO.
I think you are underestimating RR. Their top 3 in Butler, Smith and Samson will take them far. Remains to be seen if Stokes can plug a gap in lower order as a finisher or not even though he does not seem to be suited to play the destroyer/finisher role anymore. Their bowling is at least better than RCB and Punjab.
Even Chennai will be in the mix and I disagree that they will be out of running so soon. Mainly because for starters Faf seems like he is the best touch out of all the batsmen in the league right now. They just desperately need Rayadu to find form. Bowling wise, Dhoni will get the best out even a somewhat average unit now.