I would take what I keep in the trunk all the time: a quart of oil, a couple of spare filters and belts - if you've got the original tool kit, you don't need anymore tools than that. If you think you need more than that, either you know your MB is not well cared for or you are the worrying type.
We've been driving both our MB's (since new) for a combined 50-years of motoring and still think nothing of hopping in them and heading down to the coast or 1/2 across country. Why? Because they both have had 2K oil changes, 12k valve adj, 30K trans service, etc. and they are extremely low mileage - less than 10K per year - what's to worry about?

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Houston, Texas
1984 300CD 235K miles, Elvira, one owner
1987 300TD 180K miles
1974 TR6 78K miles Sarah Jane, one owner
OBK #27