On mine I turned up the oiler 2 turns from the start. It would be wise to them measure your oil consumption and make sure you didn't go too far. Adding oil to the fuel tank isn't necessary if you turn up your oiler properly. I did the TRS Skidoo thermostat update, I would definitely do that. When I start mine for the day I let it idle until the coolant hits 100 F and then shut it down. Fire it back up when I'm about ready to ride and let the temperature stabilize and go. Any time I start it during a ride I let the temperature stabilize before taking off. After the initial warmup I'm not as particular about what the temp is, just that it has stabilized.
I added a tether, bumper and upgraded the ski rubbers. Have a spare drive belt and maybe a QD belt. My QD belt made it 1500 miles. So far it is a great sled!
Also, if it hasn't been done yet you will probably need to adjust the front track shock to your liking. A lot of them come from the factory loose and the front of the sled feels planted. Tighten it up and keep going until the sleds feels out of control and then back it off a little.