Your Sport 1000 looks good TLit . The dealership that I worked in sold Panasonic bikes. This bike was toward the lower end. It's a good bike. We sold a lot of Panasonics. If I remember right the tubing is straight gauge chrome-moly. Altus shifts well if all is properly set up and the chain is not worn out. That goes for any drive train.

Since being on BikeForums I've become more aware of chain wear and the harm that a worn chain can do. Check the chain. Look online for the various ways to check a chain. Brake pads can harden over time. For now it may restore some grip by sanding the brake pads. You may want to add brake pads to your list of thing to get. Everything else is check, lubricate and adjust as needed.

The Grap-On grip might be due to be replaced as well. Some people like them, since they do provide a cushioning and some don't. Are they foam grips? If you are going to use cotton tape, Newbaum's is a favorite around here. That is up to you.