Hi, people,
Just to express my opinion on this
Deathlok - a) African-American (at least one version, Luther Manning, I think), b) he IS a weapon for the military c) not connected with previous established characters which makes him perfect for adaptation (no continuity baggage), c) heavily armored cyborg/zombie/assassin with lot of guns (think of the possibilities!!!)!
Black Panther - a) African-American, b) awesome warrior/king/military strategist/leader, c) action-adventure (awesome lost super advanced city in the jungle setting, haven't seen that in Marvel movie so far), d)again no continuity baggage
Power Man/Iron Fist - Heroes for Hire - a) Team/team up movie, b) characters are pretty awesome if done properly, c) Power Man is African-American, d)again no continuity baggage
Why make War Machine then? His main story was pretty much over, and he would not work without Iron Man!
Deathlok would, in my opinion, be much better movie than War Machine! Easy to tie into existing continuity (military secret experiment Universal Soldier style, ultimate assassin commissioned by the government, made by AIM, grafted Stark tech in the super-soldier, he can be the symbol of the Stark tech becoming perverted and twisted.... possibilities are endless!). Now, I know that the Deatlok is from alternate future thingy, but the movies can do away with that and make him the part of the Marvel movieverse!
Sorry for bad English!