What are you going to do before CP5? What are you going to do about the vehicular counters there are before CP5?
For USF specifically to fight JLI in their current state, you need to pick Armor or Mechanized and spam out a lot of CQC troops. Airborne and Heavy Cav don't work as well as you've only got one CQC squad which they'll kite with Sprint until it has to retreat. You can forget about other commanders entirely.
JLI as is is like Advanced Emplacements: there's a specific counterstrategy (CQC spam) that hard counters it, but do anything else and you'll have a bad time.
Seems like Rifle Company will be viable with the sprint that gives to Riflemen.
So, if Cavalry and Airborne don't work against them, which Commanders are good against them?