I have a 15 year old Craftsman and the only thing I've ever done is fill the gas, change the oil/plugs, and replace the wear bars. Three things I've learned over the years.
#1 Replace the steel wear bars with the rubber ones
#2 Lubricate the chain. It didn't cause any damage but I didn't even have a clue that I should be lubricating the chain. I was looking through the owners manual to see what spark plug I needed and noticed it's something you should do every year. Woops.
#3 If you're thinking about getting the bigger/better one, do it. I've never thought to myself "I wish I would have gotten the smaller one".