Hiii! Which hero should I play now?

I'm quite bored and want to start conversation AHAHAH and I just have one question. Over the course of all the events, I've received many heroes. I was just too busy maxing Invisible Woman and making Scarlet Witch better even though I have not much knowledge on all the technical stuff of making a hero better. Anyways, I now want to move on to a new hero and start working on that hero. Problem is: I don't know who. Help me choose, please!!:D

1. Black Cat
2. Captain America
3. Colossus
4. Doctor Strange
5. Ghost Rider
6. Iron Fist
7. Silver Surfer

*they're all at different levels as I've tried out each of them but I really want to know the fun factor from people who have played each hero -- thanks!