Frankly, RG is a pointless card with only one benefit that is 12 lounge access even using PP. Even your addon card holder can get a PP but they can't be swiped together. It's lounge access catalogue is as expansive as Infinia. Reward rate is dismal unless you use, Myntra, nykaa, Reliance Digital etc.
If I were you I would stick to Millenia unless you can further climb your way to DCB within the 1st free year.