How would you rate created (but real-life) players realistically?

[etnies55]

So I'm using the Jacksonville Jaguars for my franchise and I, like a bunch of you out there, want my team to be as accurate as possible. I understand that with the new expanded rosters they will most likely be close to 100% once the next roster update comes out. However, (1) I'm antsy and can't wait and (2) if the rosters aren't 100%, I'd like to know how to fix them.

So...my question is, does anyone have any methods/formulas/ways-of-doing for creating realistic ratings for real-life players that I've created that happen to not be in the game. For example, if the Jags decide to keep one of their FA Rookies Jalil Johnson at CB, but he isn't in the next roster update, how would you go about creating realistic ratings for him?

I've tried this on my own before, but I feel like there might be a better method out there than just randomly moving sliders based on a wild guess.

[Jibbler]

Usually I read a bit about the player online, get to know if hes a speed type player a shut down corner etc, thats usually how I do it a lot of reader, I find it lots of fun, I know lots of people can't be bothered and want EA to update it all but I don't mind doing it