New, wider pavement will be nice. 3 more interchanges is also good. Overall this will be a decent, yet modest improvement. It doesn't sound like the freeway would be extended all the way to Getwell Road even though that's what really needs to happen. A 6-lane freeway flanked by frontage roads would be the best solution.
From the MS state line to Getwell Road there's all these intersections with US-78:
Davidson Rd (traffic signals)
-----no driveways up to Holmes Rd
Holmes Rd (traffic signals)
-----7 driveways up to Tuggle Rd, 3 WB, 4 EB; 1 median crossing.
Tuggle Rd (traffic signalss)
-----16 driveways up to Shelby Dr, 5 WB, 11 EB, 4 median crossings.
-----Pleasant Run Rd (no signal)
Shelby Drive (traffic signals)
-----4 driveways up to Pleasant Hill Rd, 1 WB, 3 EB, 3 median crossings.
-----Stepherson Rd (no signal, BNSF intermodal entrance)
Pleasant Hill Rd (signal, BNSF intermodal entrance)
-----Sonoma Cove (no signal, Williams-Sonoma entrance)
Concorde Rd (traffic signals)
E Raines Rd/S Perkins Rd (existing partial cloverleaf interchange)
S Goodlett St (no signal)
-----5 driveways up to Winchester Rd, 2 WB, 3 EB, 0 median crossings.
-----Homewood Road RIRO
Winchester Rd (traffic signals)
-----16 driveways up to Winchester Rd, 7 WB, 9 EB.
-----Clearpool Circle Rd, South (no signal)
-----Clearpool Circle Rd, North (no signal)
-----Willow Wick Drive (no signal)
Getwell Rd NB Entrance/Exit (no signal)
Getwell Rd SB Entrance/Exit (traffic signals)
The last 2 miles of US-78 leading up to I-240 is quite a clusterf*** of driveways and intersections, including 5 more traffic signals. The upshot is most of the property is commercial, not residential. None of it is post card material. A bunch of it looks kind of run down. It might not be as difficult to buy out properties and acquire right of way as it is in other better looking locations.
Still, even if property owners along US-78 are more than willing to sell, it's still going to take a whole lot of money to extend what could be I-22 the rest of the way to the I-240 loop.