Body, if you don't plan on using TTL flash then the plain Pro should be just fine. But it is a bit older.

Finder, the non metered prism finder is what I started out with, and it is very nice. I eventually bought the Reflex finder for the meter when doing macro. It's ok, but has a lot of distortion compared to the prisms. Eventually I found a metered prism that was a bit ugly (matte paint chipped off, so it's a glossy black finish now), but worked perfectly. I wish I had just got the metered prism to start with.

Focus Screen, I didn't care for the stock screen indoors. I found an Beatie Intenscreen and it really makes focusing easier.

Winder, normally I just used the hand crank for landscape and macro work. But I bought the camera with the smaller winder. It's very nice if you want to keep you eye up to camera for a portait session. The WG401 also has a cable release socket on it. But it's much heavier with the AA, which is why I went for the lighter WG402. Battery cost isn't much.

Lenses, well that's personal. I think you should add a wide angle to your list eventually. I never used the LS lenses, but if you shoot with flash then you probably want these. You may also want the Pro TL then too.

Definitely need caps and a bag. And each of your film backs should have a darkslide. You will want two backs if you want to switch film types. If you just want to load quickly, get some extra inserts.

Now for the shameless plug: If you're interested I've got a Pro TL with lenses and a buch of stuff for sale here: