I can see AA adding PHX and maybe even a very very very slim chance of BOS. DL should add SLC back. UA just needs to add IAD and I believe they are complete unless they want to give LAX a try. F9 should add a few more cities too. UA to IAD and AA to PHX seem the most likely,
XNA got the CRJ 550 the first day of commercial service between here and Ohare. I think it is on every frequency. They want all eastern connecting traffic thru ORD outside of EWR on that plane it seems.
XNA is getting up among the airports with WN service, plus the airport is growing as is the market, it is not mature in way, shape or form. It looks to surpass Wichta after 2019, if not, will in 2020 for example. Some believe it will not happen but one poster here said they were coming pre MAX debacle but had issues with the FBO at XNA. The Allegaint BNA flight shows some amount of leasure travel so DAL, DEN, MDW/STL and BNA seem like very safe, logical adds if and when they come into the market. I could see HOU and LAS/PHX added in short order, MCO is there as well.
I can see Frontier shifting a flight like ORD-XNA-DFW from Branson as it seems to not be coming back there to expand XNA and adding MCO. Pretty much the same kind of routing, timing.