A good friend of mine has had a series of Chevy trucks and can't figure out the A/C either (he hits the "off button" which I think merely shuts down the display). In the meantime he introduced me to the ZTR...he's on his second Dixon.She has had the same car for nine years but cannot turn the air conditioner on. She does NOT need a ZTR to figure out! She would get hurt on one. I am looking at price here for the cheapest mower with power steering.
A few years ago I got her a battery powered weedeater and leaf blower. It was perfect for her. Weedeat until the battery went down. Then sit in the shade while it was charging. Takes her all week to mow and do a little weedeating. Ticks her off when my sister and I come and do the heavy trimming about once a month.
K.I.S.S.
Time to man-up Eddy...my ZTR (Hustler) will go as fast as the machine will let it go. From there it will go as slow as I want it to with low-impact movement of the levers...and it has a cup holder! But now you have set up a challenge...my MIL is 88 and has a big front yard with no obstructions...I'll see if she would mind being a guinea pig.Before buying my zero turn, I had a riding mower that I really enjoyed. The riding mower was relaxing and fun to mow with. It was slow, and it couldn't handle side slopes very well, but I always looked forward to having a beer on the fender when on it. My zero turn is all work. It beats you up, it doesn't alloy you to enjoy a beverage and it's not relaxing. My 79 year old dad refuses to get on it after trying it for ten minutes.
Power steering is where you have me struggling to give advice. I don't know of any riding mowers with power steering unless you go to a diesel sub compact tractor with a mid mower deck. That would be really nice and easy to operate, but also super expensive.
Have you looked at something like the Snapper riding mowers? I borrowed one once and enjoyed it.