Sarge:
yeah, it sounds like you just hit on a couple of bad kits there...
have you checked out the On The Way site yet ? dedicated 1/72 armor site with lotsa great info on there for us newies ! (no airfix on there, 'cause it's actually 1/76
according to them...a purist, i guess)
as far as dioramas go, first try and imagine a scene in your head. battle mode or resting between missions, refueling or checking a map. where would the crew be, and what would they be doing ? try and pose figures so that they relate to one another. size the base to fit the elements of the scene, and pose the star of your scene at an angle to the edges of the base.try to put in some differences in elevation in groundwork so it doesn't look like a ping-pong table...
check out the dioramas section on this site, too.
frosty