I'd check the turbo too. My SDL slobbers on the compressor side. Bad enough for a haze and smell, but not bad enough to smoke out the traffic behind me. Check for oil in the turbo intake. If you don't have a ton of blowby, it's probably the turbo seals.

Rough start could potentially be a dead glow plug.

__________________
Current stable:
1995 E320 157K (Nancy)
1983 500SL 125K (SLoL)

Gone but not forgotten:
1986 300SDL (RIP)
1991 350SD
1991 560SEL
1990 560SEL
1986 500SEL Euro (Rusted to nothing at 47K!)

Gone and wanting to forget:
1985 524TD 167K (TotalDumpster™) [Definitely NOT a Benz]