One thing you didn't mention is about different film types. Different color films have different colors/temperatures. I am not the expert with color film that I am with black & white (I don't shoot b&w orchids) but color temperature can make all the difference as to whether you will get true to color pictures or not when using film.
Also, there is a Nikon SLR out there for under $300 that is excellent. You get the Nikon optics and a much lighter weight plastic body. It comes with a 35-70mm zoom lens and fits all Nikon lenses. So it's easy to pick up a used lens somewhere on the market. I've had one for several years now and I LOVE it.
Randy
