Now played 7 games with Ferals, fun in slow kind of way...

Makes it all the sweeter if your orkeosaurus actually gets into combat though. Agreed that wildboyz could do with being slightly cheaper. The comparison to normal warband is not favourable in most circumstances.
This list or similar is what I have been using and seems to work ok:
-3 Steam Gargants
-Warband, Orkeosaurus, Wyrdboy, Boyz
-Wildboyz, Orkeosaurus, Wyrdboy
-Warband, 2 Squiggoths
-Warband, 3 Catapults, Wyrdboy
-Warband, 3 Catapults, Wyrdboy
-Junka Brigade, Nobz, Wyrdboy
-Junka Brigade, Nobz, Wyrdboy
-Big Boarboyz Horde
As has been said Steam Gargants are crucial in ability to threaten/defend. Orkeosauruses slow, often out of action but pretty invulnerable transport, except to firefight, or critical stumble if into impassible terrain (like buildings = instant death!). Boarboyz seem to generate much fear. Still having enough stuff to capture and screen enemy blitz and another take and hold (preventing enemy contest) while defending own objectives is tricky and a 4th turn affair. Preventing enemy winnning easier though. Junka truks fabulously useful due to speed. Difficult terrain problems do seem a bit crazy sometimes - eg charging boarboyz into woods is dangerous!?
Some other 3K list ideas that I'm tempted to try out:
-3 Steam Gargants
-Warband, Orkeosaurus, Wyrdboy,
-Wildboyz, Orkeosaurus
-Wildboyz, Orkeosaurus
-Warband, 3 Catapults, Wyrdboy
-Warband, 3 Catapults, Wyrdboy
-Junka Brigade,
-Junka Brigade,
-Uge Boarboyz Horde
-Uge Boarboyz Horde
Orkeosaurus and Boar Horde...-3 Steam Gargants
-Warband, Orkeosaurus, Wyrdboy
-Wildboyz, Orkeosaurus
-Wildboyz, Orkeosaurus
-Wildboyz, Orkeosaurus
-Wildboyz, Orkeosaurus
-Uge Boarboyz Horde
-Uge Boarboyz Horde
-Big Boarboyz Horde
-Boarboyz Horde
My full 5000 point list I have painted up...
-3 Steam Gargants
-Warband, Orkeosaurus, Wyrdboy, 2 x boyz
-Wildboyz, Orkeosaurus, Wyrdboy
-Wildboyz, Orkeosaurus, Wyrdboy
-Wildboyz, Orkeosaurus, Wyrdboy
-Wildboyz, Orkeosaurus, Wyrdboy
-Warband, 2 Squiggoths
-Warband, 3 Catapults, Wyrdboy, Nobz
-Warband, 3 Catapults, Wyrdboy, NObz
-Junka Brigade, Nobz, Wyrdboy
-Junka Brigade, Nobz, Wyrdboy
-Uge Boarboyz Horde
-Uge Boarboyz Horde
-Uge Boarboyz Horde
-12 Madboyz
-Warband (or upgrade all Wildboyz to Warbands)