The second pic doesn't look great but I'm not used to looking at broscope pics so hopefully more chime in. The intake valves count too, maybe more. The more carbon that can absorb fuel the worse the problem can be but it's not an exact science. Chrysler had an excellent foam spray (meant to spray in the carb/throttle body with engine running) for carbon back in the day but I don't know if it's still available. I think some of the pro-type (into the injector rail) cleaners work pretty good for carbon too. Your biggest friend is PREMIUM gas.

Just to make sure you are saying more of a tip in slight stumble or hesitation , not bog, right?
Did you verify how the IAC motor works off idle ??

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1988 325is (purchased new) sold
2004 X5 3.0 2005 X3 2.5
2008 X5 3.0 (new to me)