Eyeman thanks, you made me think.
Lots of 1M owners, including me, loves this car as it is. It has a superb balance quite rare to find in modern cars. I call these little mods like small corrections basically. When the 135i came out in 2008 I wanted it to be a bit more blunt and complete, I thought that was the right step but BMW left the job halfdone. Then when they built the 1M, I bought it like I was waiting that day since a decade or so. So, the mods for a 1M are only valid for me if they strengthen the stock car's essential qualities and make it more reliable. Moding 1M to make it something else is not on my agenda.
I have the traction and grip car (or myself as a driver) needed provided by PSS.
I have slightly better ride quality again thanks to PSS.
I will have the ER charge pipe, no need to wait for an occasional pop/crack plus it will make the throttle response better.
I may have better clutch feeling and more natural 1-2 shifting with CDV delete, will see that one soon. I have little complaint about the stock shifter and clutch but if it will be even better will worth the effort.
I consider drone and lack of a good sporty sound at full throttle as issues and they are beautifully resolved by N55 mids and Evolve Race muffler combo. They also made engine more responsive and free(er) revving.
Since I don't have any other real complaints or wishes about the stock car, I better stop there anyway. I think I will just just stick with the stock diverter valves. You said it good, no need to overkill.
2011 BMW 1M: Euro spec, w/out Nav, manual seats. Evolve Race+N55 mid, Michelin PSS, ER charge pipe, aFe ProDryS drop-in filter, CDVx, BMW-IND trunk spoiler matt cf/VO stripe, BMW blacklines, BMW black grills, IND side gills&rear M logo, silver turn indicator bulbs, anthrazit overlays on side creases and on air curtains, MPerformance steering wheel w/VO ring, BMW steel pedals, custom mats, color matched MPower e-brake.