35* swings are reasonable. if you check your oven temperature swings (if you have an electric oven in your kitchen) you'll see similar swings.
when i get my # 3 i hope i get similar performance to yours. that is the temps are a little higher than your set temps , that way you can actually crisp chicken skin at the highest setting.
it would be a lot worse if let's say your swings happened 30 degrees below the set-point.
my advice, just set it at a lower settings and monitor the average temps with your Maverick.
also my guess is that any pan in the lowest shelf settings will get the thermostat to cycle quicker, you may not even need to put water in it. the pan effectively traps some of the heat at the lower area of the oven where the temp probe is thereby getting it's temp up faster.....
as soon as I get mine , i'll do some simple mods i have in my mind and let you guys know of the results.