I go the opposite route. I don’t like seeing heroes on my team with weaker stats than their equally leveled counterparts. If I have two 4* heroes at 4/70 and one has 1500 hp and the other one has only 1000 hp, my instinct is to boost the hp of the 1000 hp hero. Even though the 1000 hp hero might have a much higher attack than the 1500 and it might be in my best interests to boost his or her attack skill even more, I prefer to make the hero less squishy. And vice versa in the case of a hero with a low attack level.
That might not be the best strategy, but I’ve always been more of a jack-of-all-trades, master-of-none kind of person, and that’s also how I usually set up my gaming heroes / avatars.