Well I guess we answered the question of whether or not this is a pointless discussion.
Dale, Thanks for jumping in and giving us some good things to think about. I agree about one thing you said, often the things that we look for to make the game more realistic are only making the game harder. I think without a significant increase in technology (and also a great increase in cost) this game is about as "realistic" as it can get. Therefore the things that are looked for to increase realism are only increasing the learning curve. This game could easily be made so that only those with a significant amount of flight sim experience, would be able to play it.
That being said, I still think that we need distance in numbers, at longer ranges, over 1k or so. The use of variations in shades of color is ok, but much harder to interpret. "Hmmm is that light, light red, or is that light, light, light red?" I like the idea of the plus and minus to the range icons. It is something that would be quickly understood, and very easy to interpret.
You could also do range in RED when they are closing on you, and range in BLACK when they retreating from you. or something like that. I don't like having to "read" icons, it is nice, if just seeing them there in your field of vision relays enough information to tell you what is going on. If shades of color were to be use, I think you need two separate colors, one for closing and one for receding.
I don't envy Dale and his crew. They have to come up with a game that not only challenges the experienced, but is easy enough the new guy wants to stick with it.
Good luck to you guys, I hope we are helping you with all these ideas.
