This was my first experience with the Kalamazoo Marathon and I was not disappointed at all.
Packet pickup and Eco is held on the day before (Saturday) the race and the Wings Center. It is located right off of I94, so it is real easy to find. The expo isn't large, but for the size of the race, there were a lot of vendors (probably 15-20) mostly consisting of sponsors and other local races. To get to packet pickup, you had to wind your way around all the vendors but crowds were not an issue. Even had a place for family and friends to make signs for the next morning.
Picking up your race packet was easy. If you were not happy with your shirt size, they did have a exchange (if they had your desired size remaining).
There are not any hotels located by the start/finish area. I would suggest going to the host hotel in downtown Kalamazoo. It is probably about 2-3 miles from the start but it is the cheapest if you register with the discount code and it is s nice hotel. Even had water, bagels, and fruit out for the runners on race morning.
The race location was easy to find and there was plenty of parking within a very short walk. At the starting lines, Pacers arrived early to help runners figure out where to start from. After the national anthem, the race started promptly at 8:00. The half marathon and marathon start together and run together for 3.5 miles. First few miles are easy but there are hills later on the course. A few of the other sites around the course are downtown Kalamazoo, Western Michigan University, local neighborhoods and parks. Course uses all roads early but some bike paths later on. Vehicle traffic is very well controlled by local law enforcement. The course is not totally closed off to traffic but runners are given plenty of room to run.
My favorite part of the race is the neighborhoods. A lot of families had parties out in their front yards and were cheering the runners on as they went by. The toughest hills were at mile 9 and 22. Another great aspect of this race is the Bacon Station (around half way, only in the full marathon Course), Gimmy Bear Trail (around mile 18 I believe), and Popsicle hill (mile 22). Nice reward on the last real tough hill on the course. Along the last mile, crowds really started to form along the streets to cheer on the runners.

Pros

For this being a smaller marathon (not too small but also not a huge race) the support from local residents was fantastic. Families just came out on their lawns, watched and cheered as runners went by.
The local police departments did a great job of keeping the course cleared of cars. Since I wasn't running all out, I made sure to thank as many as I could.
Aid stations were great, spread out very well and had plenty of volunteers.
Challenging course with enough hills to keep you honest. It was also very beautiful course as well
Live band at the finish
It was easy to find parking before the race and easy to leave after.
There was post race food which included water, fruit, and chocolate milk.
For $8 you could purchase a hot dog, veggie burger, or BBQ Chicken meal. Also came with a drink. If you did the Half and Half or Mitten Challenge, this Meal was free. If we didn't get it for free, it would have been worth the $8.
Popsicle hill was awesome!
Nice looking shirts
Free race photos to download after the race
Very well marked course
Easy expo to navigate, packet pickup was easy. Also had a chance to exchange shirt sizes
very energetic announcer (hey, he at least tried to say my last name as I finished)

Cons (this will be short)

I love cold chocolate milk after a race, but for some reason, they got the chocolate milk out before the race even started and left it sitting out on a table. There is a 5k and 10knoption as well so I am sure they wanted it out for those runners, but keep some in the cooler for the marathon and half marathon runners. Mine was warm.
If you don't like hills, then this may not be the race for you, but even that wasn't too bad.
There were a couple of boring sections of the course but what marathon does not have those? Running on Western Michigan University Campus was one of those spots. Students are gone for the summer and it's not a very attractive campus.