I'm a scale nut and I base it around the Diaclones.
I have most of the G1 Autobot cars on display though I use one or two updates like Robotmasters Mirage and Make toys Inferno.
Basically whatever I feel scale reasonably with G1 Prowl and Co.
Examples include:
Fansproject Stunticons
CW Seekers
TR Hardhead
TR Highbrow
Classics Nemesis Prime
Oversized CW Rodimus
G2 Laser Rods
G2 Stormtroopers
FP Rodimus Prime

Other G1 figures I include:

Scorponok
Snapdragon
Soundwave
Battle chargers
Ultra Magnus
Scourge

 

I display my g1 insecticons with my chug insecticons. I use the g1 versions as the true characters and the chug versions as the clones clones clones.