Yes, look for the obvious things first: fluid and filter, and also check the kick-down cable and the little vacuum line on the driver side. I've never had a problem in 140k miles on my '91, so I don't know how/if these items will affect the shifting quality, but they are a quick place to start. To adjust the kickdown cable I THINK you do the following (a senior moment on my memory);
pop the cable loose from the throttle linkage at the ball joint attachment, push the cable back, then gently pull it out of the trans until you feel a resistance like it's starting to pull the linkage in the trans, then if it's adjusted for correct length, it should just pop back on the ball on the throttle linkage. If necessary adjust it for length until it does this. Sombody help me if i got this wrong.

Oh, some areas to check on the SE for potential repairs/maintenance (not related to trans though):
- motor mounts collapsed
- engine fan pulley bearing shot
- head gasket leaking water (or oil, or compression).
- ball joint and steering linkage grease boots cracked
- front "u-joint" or coupler shot
- the infamous front timing cover oil leak
- valve stem seals causing oil usage
- then there's the usual brake pads, rotors, and real mufflers every few thousand miles.
- And of course, if you have to replace the short water hose between the head and the water pump - JUST SELL THE CAR.