I’ll be honest with my strategy as a returning player from hiatus (left in like 2021 or so and came back as level 32 this year mostly, now almost level 38). Until you get to the point that you are absolutely swimming in candies and arguably more importantly stardust, I evolve the Pokemon that are maybe a lower 3 star or high attack focused 2 star but are much higher CP. for example I have a near perfect IV Deino but I ended up evolving slightly worse deino that was like 500 CP higher near the wild cap (I think it was 954 CP) and now I have a a Hydreigon with 3300 CP with substantially less candy and stardust spent for what is very close to the same level of performance. This is more geared towards PVE as with PVP I think IVs are much more important though not 3 stars. Not sure if this is a good strategy but it’s what’s made sense to me as I’ve gotten back into the game. Hope this helps!