Lol, as you can see, there are lots of ways to do it. If it was me, I'd run it as a wet/dry sump, and just have the canister on there as a spare, rather than to really filter. However, what Mystic's saying will work just as well, and she's totally right, you can NEVER overfilter, so if you can, add a nice big canister and you'll have an awesome nicely filtered tank, AND a spare filter.
If the baffles are out, just add the media into bags (like orange bags or something) to keep it together. There's no real reason to add them once they're out, as you can hold the media in things to stop them getting mixed up and keeping them easy to clean.