If you need the rebounds then yes, you may lose some in points but Evan has been picking his scoring up, I think its a close one but it might be worth the gamble as its not a huge gamble cause you will get more rebounds in return anyway
In my league, you'd be crazy to trade Ellis, but in this case, his 3% is so bad that you must do this. Basketballmonster rankings with your categories show that Ellis is 14th round value and Turner is 5th.
Some other players that jump up in your league specific ranks are Kidd, Anderson, Richardson, Ray Allen
The way I saw it, he is almost crippling in that category. 4th worst in the NBA, but that is taking his current stats and not adjusting for a certain increase in his .188 3%. He has a slightly worse affect on 3% as Faried and Josh Smith on FT%. Not close to Dwight Howard level but really bad.
I would do this....I think Ellis is a couple trick pony with an injury history and I love the way Turner has been playing and has played in the past. Turner has more versatility and less of an injury past....grab Turner!