Lisa,
Congrats on your upcoming trip to Italy! Great questions about MCI-Italy airfares, and you're right that the prices jump around a lot. MCI is my departure airport as well. When I flew to Rome the first time, I wound up paying ~$1100 for a trip in October 2016. As others have noted on this thread, until the upcoming Icelandair arrival, KC tends to be a higher price point airport.
With that said, I strongly recommend signing up for the premium membership for Scott's Cheap Flights. MCI appears on a handful of fare sales throughout the year, mostly for destinations in Europe. When those sales pop up, you can snag tickets to Rome for <$500. That's how I flew to Rome in 2017 and here soon again this year. I even added on the Delta Comfort+ seating for the transatlantic portions of the flights, and the tickets were still quite good for MCI standards (~$800 including Comfort+ seating, before that the ticket was $575 to give you a frame of reference).
Also, sign up for the Hopper app. You can set the app to monitor flights for certain destinations and date ranges up to 11 months out. You get weekly notifications of how prices are fluctuating, especially for major sale notices. Hopper is how I found out about cheap tickets to Scotland and is the reason I'm able to budget 2 trips to Europe this year - woohoo!! I monitor both SCF and Hopper alerts closely. One word of caution: Those major sale notices tend to last anywhere from 1 hour to 24 hours. You have to be prepared to make a quick decision when those notices arrive. If it fits your plans, go for it! If not, you have plenty of time and keep monitoring.
A last recommendation... Don't let the anxiety of picking perfect seats for a flight drive your decision. The reality is that planning and purchase airfare has a margin of error, let alone margin of risk. If the cards align, great! If not, find a next best alternative for the flights and enjoy your time in Italy... which is the goal in the end, right? ;-)
Happy planning and let me know if I can help with any additional KC/MCI flight questions. I've done the puddle jumper option out of KC before as well, so can speak to that if you need.