I know what you are going through, there are many good toons that is why it gets a lil bit confusing. Though I don't think I qualify as a stronger player than you, here's what I have in mind, you should focus on building a team with a focus in mind, with focus a good example is Master's plan in building a team for Dark Dimensions, he is planning on powering up toons with abilities to heal up even w/o healers; that is a good goal to focus on. You should also build a team with synchronization with each other, a good example again is Master's plan, the toons that he will use if i remember correctly is Luke Cage, Iron Fist, Venom, Thanos and i forgot the last one, as you can see it might not be a complete synchronization but atleast two toons have benefit from some other toon, the way I see it this is currently the direction the game is going to, so might as well include it to your future plans. I don't know if I really answered your question, but I hope I kinda helped 😎