Fanku Kaibutsu, you deserve a pat on the back. You've brought up many excellent ideas that SHOULD be used in the new comic. You da' Ghosthead.
No ECTO-2. No ECTO-3. Although ECTO-4 would be nice to see sometime down the road, maybe. But definitely not those first two I mentioned. They seemed a little too far-fetched. Especially considering that the guys probably wouldn't have all that much use for them, anyway.
Taking characters/episodes from RGB and modernizing them for the new comic would be GREAT! Characters/Ghosts/Monsters I'd like to see:
Charlie Venkman (Peter's Conman Dad)
Inspecter Frump (The Police Lieutenant who always gave the guys trouble. Sort of like a Harvey Bullock rip-off. :p )
Walter J. Peck (The Movie version, only. Not the way he was on RGB.)
Cthulhu
The Headless Motorcyclist
Casey Jones
The Earps
The Boogieman
The Sandman
Samhaine
Episodes I'd like to see:
No One Comes To Lupusville
Egon's Ghost
The Boogieman Cometh
Mr. Sandman, Dream Me A Dream
When Halloween Was Forever
X-Mas Marks The Spot
Halloween II 1/2 (Without the Jr. Ghostbusters. :p )
The Bogeyman Is Back (Without the Jr. Ghostbusters. :p )
It would be cool to see how these situations would be in the comic.