http://goallineblitz.com/game/replay.pl?game_id=192798&pbp_id=3872140This play shows why vision is probably THE single most important attribute when building a linebacker. It seems like a lot of people here are trying to build a free safety build and have him play linebacker.
There are a few good ideas in this thread, however. Tackling is highly overrated if you have decent enough strength to cover for it. I have my player at about 36.5 strength and tackle is nearly soft capped. If you have a LB that has 20 ST then you may as well put him at DB because what you have is a guy who is never going to get off blocks and will only get tackles if nobody goes to block him or he beats the blockers to the ball.
The better league that your player plays in, the faster the linemen and TE's are. If they beat you to the second level you're going to need some strength to break off the blocks. You can get away with low strength on LB's in average leagues but the better the blocking gets the more your LB will suffer.
Agility and Speed should be about 3/4 in favor of Speed. In the play above you see all three attributes used in Speed, Agility, and Vision. My player saw the sweep coming and went under the pulling guard and made a play. That is what you need.
NEVER put points into catching. If you want to train it, then fine. My LB has 6 career picks and 2 for TDs without ever having put points into it. Interceptions are all about right place and right time. It is a total waste of points to put them into catching. Again, you're not building a free safety. You're building a linebacker. The bulk of your work is going to be making the tackles.
Unless your coach likes to use you in blitz formations, which mine never has, you need to fill up that Hard Hitter attribute bar as hard as you can. Unless you're playing MLB the defense general points shouldn't be too high but you can never go wrong with as much diving tackle and monster hit as you can. My player has forced 12 fumbles in his last 30 odd games. All on wrap up tackling.
Blitzing from the linebacker position in the sim isn't an exact science yet so I don't see the point in building a linebacker for that purpose.
Linebackers need to be all around players in this sim to be effective and there is no one right way to build them. Speed, Agility, and Vision are important at virtually every position but do NOT neglect Strength and Tackle as is being advised here. You'll get eaten alive in very strong leagues that way.
