please, talk to me about robot drive

[Dasistmeinmoped]

sure figuring out gear ratios, max pushing power, current pull and such was pretty easy, but setting up some wheels to do the job.. not so much. I have been trying to research some drive designs but seem to be hitting a brick wall in my progress. to make this easier to read here's just a list of design ideas. PLease comment slash ad!
-6 WD - saw design with all traction wheels all wheel contacts coplaner
-6 WD - Drop center, all traction we prototyped this and found it near impossible to turn while stationary. The center axle was dropped 3 washers (french national measurment, its real look it up..) which was about 3/16" i believe
-8 WD with some funky mechanism that lifts the front, and rear wheels off of the ground as to shorten the wheel base.
-6 Wheel swerve where the front and rear wheels move up to 80 deg. (view mars rover)
-6 WD coplaner- middle and rear traction, front omnis <-(prbly will proto type this withing the weekend)

thank you for any input. We are looking to have a strong stance on the field, so in any design some amount of tractionwheel is desired.

matt