The easy way would be to just put them all back at the same time, maybe add a new car with a kit as well, like the GR Yaris or GR86.
But that's clearly not what's going to happen.
Or even a new kit/kits for an existing car.
The RX-8, ND MX-5, R33 etc could definitely use them.
On a different note - my random speculation for the day;
The Nissan Sentra B13 (or Tsuru) will be added in the Elimanti update coming in December.
I think it'll be added into the Autoshow, much like the Supra RZ was when it was reintroduced in the Eliminator update in FH4.
The exclusive "Eliminator limited edition" car referenced in the leaked audio files I think will be an custom version of the Tsuru, specifically tuned for Eliminator - with custom parts etc.
I also think one of the new starter cars for Eliminator will be the Tsuru too.
EDIT: Bonus out there wild prediction. Isha's taxis (or a new taxi company) returns with this as the hero car
This post is brought to you by procrastination at work, never fails.