Confused about player rating

I'm in the 5th season of a save using all regen players and I've somehow won the league with Arsenal in every one of those--the last time by almost 30 points without even really trying. I've obviously been getting kind of bored with it and am in the last year of my contract so I've been simulating through most of the games to ply my trade elsewhere, which brings me to my point.

I know I can set the tactics and line-up for my assistant manager to use, but his insistence on certain players over others, and all of the scouts on my team agreeing that they're the best option, has me a bit baffled.

For instance, what my scouts and coaches tell me is my first choice central midfielder:

Dean Derry

My best scout's assessment.

In that last image, it says there's not too much difference between him and Silva, which is essentially Kaka's regen that I signed this season from Milan on a free.

Silva's stats.

Is that right? They're almost the same? Dean Derry has 8 assists all year, and in the three years I've had him, that's been his best total. There's another MC I have that is 22 years old, named Gaulberto Carrillo (his stats) that my scouts advise I should sell as soon as possible and never even involve as a substitute when I let them select the line-up--but he's made as many assists as Derry and even scored a few.

WHY is Derry ranked that well when it's quite apparent he's not? I understand, high passing, technique, and creativity, but it isn't paying dividends.

Another player I bought (for 500k pounds 4 seasons ago) is a striker that has played primarily in domestic cups and any spare Premiership/Champs. League games that I've had after winning/qualifying. He has an OUTSTANDING record, scoring almost 50 goals in 61 (18) appearances for me, but is another player my scouts have insisted, ever since I bought, that I sell.

His stat's.

I understand his stats aren't amazing, but you can't argue with his goals to game ratio. My scout with 19/20 Judging Player Potential/Ability--all of my scouts in fact--deem him a 'Good Championship player'. No matter who is injured, or who hasn't scored in over 30 (!) hours of playing time, he is never included in the squad unless I hand select him.

Who is the goalscoring machine the computer suggest in a central striker role ahead of him?

This man.

He obviously hasn't been tearing holes in the oppositions nets, so why is he so highly rated and the other deemed a leper by my entire staff? He, of course, being the magic man who I just received a notice for a few games ago as having not scored in over 30 hours.

It's really no big problem, I know it's easy to change, but it is a bit annoying. I let my assistant or one of my coaches choose the base line-up before every game as I imagine they might sometimes have a better perspective than me, but I must say, seeing Diogo in the striker's role every time I do this is beginning to make me ill.

Sorry about the personal effects that appear in one of the screenshots, but I can't seem to edit it the post. I guess it doesn't really matter.

If I could live without an Ass Man I definately would, because they are useless. If I had my own way I would only have coaches and physios because the scouts and the ass men are crap.

I actually don't have any scouts because they are so god awful and I make my own decisions on the players. Well I have one and he finds players and then I decide what they are like.

Ass men, can't do team talks, can't pick teams, can't pick tactics, and make a terrible hash of judging players ability.

I have a strong feeling that comment from Ass man and Scout about a player's ability are totally based on the player's CA and PA.

As you all know high in CA not necessary mean a good player, so at the end of the day I would rather ignore what Ass man and Scout suggest. Except when it comes to buying player, scout could give rather useful indication on a player's personality and transfer price and wages.

CA and stats are a bit different.

CA states the player's ability as a calculation of his stats. For example, if he excels in a lot of things, his CA may be lower, due to his *important stats* being lower than those who are very good in those stats.

As an example, Daniel Alves stats are fantastic. However, his CA is only 170+. Thats because his stats for defending are not the best, compared to right-backs such as Sergio Ramos,whose stats for defending are very good.