2500-4000 RPM range could use a few degrees pulled. You've got a noisy number 5 but I've seen several people complain about that and somebody a valve cleaning is recommended but never saw if that fixed anything. I'd see if you can't find a little better gas, little E85 to up octane or maybe even try some octane booster. Luckily the DME on these cars is very good at keeping things in check so even though it's pulling timing it's not going to really hurt anything it's just not the best thing to do.
2008 135i - MHD/JB4, MS DP's, AMS IC, UI CAI, CDV delete, M3 control arms/Links, RE Toe Link, ECS Trailing Arm, M3 rear SF & Trans bushings, SS brake lines, Michelin PSS.