Number one death of chip leaders the world over has got to be opening up the range too much, feeling "safe" with a big stack. In reality, it only takes a few losses, doubling up others, to kill you quick. Do not start chasing all draws just because you "can afford it"; you will not for long.
What I use to determine how LAG/TAG I am depends on the table. If they are playing tight, I loosen up - if they are loose, I tighten up. You know, if someone is raising every hand and still getting several callers at this point, I'll sit back and let them take each other out, unless I got a good hand.
Also, think about calling those hasty appearing all ins. If you have yet to see one guy play a single hand at your final table who suddenly shoves his stack, look out - especially if one or two others come along for the ride. Many would gladly call with AK suited, but get real - a 3, 4 way pot? You are going to be facing at least one pair, probably big, plus another ace who might pair his crap kicker...ask if this is really a good spot to risk xx% of your stack - 10%, sure. 30-40? No way. Wait for a better spot.
I would also seek to curb my preflop all-ins (shoving and/or calling) as short stacks might be desperate enough to call with goodness only knows what, and suck out with it. I see that the most. Sure, your big ace looks great, until the shorty with J5 suited looking to get lucky does so - at your expense. They might fold to a bluff on the flop where as if all in, you have no control. It's far easier to shove preflop not knowing than to actually look at a flop where you might be drawing dead if you call.