This chassis should work fine with the system you were looking at. Like any used chassis, some standoffs may need to be moved to accommodate a different system board. I have put three second hand server chassis to new purpose with my FreeNAS servers and it takes a little more work than using brand new but if you are willing to put a little work into it, it can be a good deal. I have been using mine for almost two years now.
Not worried about dealing with issues like the standoffs or upgrading fans and the like as I am a low voltage contractor and deal with these types of issues on a regular basis. Also having built many desktop PC's over the years, it should come second nature.
I would suggest this model SAS adapter because most of the work is already done, you should be able to plug it in and start using it immediately:
https://www.ebay.com/itm/Dell-H310-...ZFS-FreeNAS-unRAID-High-Air-Flow/162729848324
This is the same model I use in my FreeNAS servers. Just make sure it has some air moving past the heatsink to keep it cool. I had one overheat and fail when I first started using them but I have been using the ones I have now for over two years with no problems.
This won't be a bad idea or problem. I am assuming that the reason for this is to accommodate the larger number of bays but as I have only worked with PC's and not servers I am not sure. I need to be educated about this.
Hard drives do put out some heat. The more drives, the more the heat. Just be sure there is enough airflow to keep the drives below 40°C. The hotter they get, the faster they die. I try to keep my hard drives closer to 30°C and I manage that just fine with my house set to 77°F and the fans in the server running between 1000 and 1500 RPM. You can make a server chassis fairly quiet but it will never be silent. Mine are quiet enough that I can tolerate having them in my office, less than 8 feet from my desk.
Note: The fans in my server chassis, when I bought them, were 5000 RPM monsters that I had to replace to be able to live with the sound.
Not worried about the noise as if I use this approach, and I am leaning this way, the server will go on my existing AV rack in the entry closet. This closet has an exhaust fan system in place already that pulls in air from under the door and exhausts it to the attic. With upgrading the existing chassis fans I think the noise will not be an issue. There are already 2 surround sound systems in this closet so noise won't be any issue. We try to keep the house about 78-79 in the hot months. The AC bill is awful, but I find when I get older, I don't deal with heat as well.
Thanks again for all the help. You have many good idea's.