If you're looking for a meeting place or a good stop around ½ or halfway between Columbus and Kalamazoo, you can try Fort Wayne, IN, which is about 2½ hours northwest of Columbus, or about 2 hours south of Kalamazoo.
Other possible places to stop near the midpoint include East Liberty, Payne, and New Haven.
About ¼ or a fourth of the way, you can stop at Holden, OH. This is about 1 hour northwest of Columbus.
About ⅓ or a third of the way, you can stop at Lima, OH. This is a little over 1 hour northwest of Columbus.
About ⅔ or two thirds of the way, you can stop at Angola, IN. This is about 3 hours northwest of Columbus, or about 1½ hours southeast of Kalamazoo.
About ¾ or three fourths of the way, you can stop at Coldwater, MI. This is a little over 3 hours northwest of Columbus, or about 1 hour southeast of Kalamazoo.
If you drive straight through without stopping at all, the total distance is 276 miles. The distances shown above don't include local roads to get into each town, so if you're planning a long road trip, make sure you factor in traffic and road conditions, rest stop breaks, and interesting detours along the way. If you're in a rush, you can do the trip with zero stops, and your total travel time would be around 4 hours, 25 minutes.