Wow, some of those portrait tats are amazing! But some are a little...mmmnope, haha.
Anywho, OP - it's always great to get feedback and ideas to stir your creativity, but please take your time in deciding what you want for your MJ tattoo. My best advice is to think very long and hard about
what it is he means to you. Many fans and friends of his all agree that he has a unique connection with all of us - even us bajillions of fans - what do you feel best represents that connection?
Mine was years and years in the making - I knew I wanted one right after the trial, but I couldn't for the life of me decide what I wanted. Nothing seemed to really fit. It actually kind of bothered me before he died - this man was one of the most important things in my life and I knew I wanted to memorialize it on me somehow, but for the life of me I just couldn't figure out what I wanted.
After he died, things started to become more clear, and as I worked through the grief, I was finally able to start visualizing something that most accurately represented him and my love for him. I ended up with something slightly macabre and not immediately recognizable as MJ-related, but it suits me perfectly. I know I want some additional work done to it and other work done around it as well, but that will have to wait until I have the money to get it worked on
So, just don't rush. A lot of these tats are great and I think would be a good foundation, but really really really truly think long and deep about it. Let it come to you! You'll know when you have it.