The oil consumption is probably one of the most important issues to ask about. Officially, to cover their butts, Isuzu issued a TSB advising that 1 qt/1000 miles was considered "normal".
Overheating seems to have become a VERY common problem in the past year or two. Most report it only occurs when A/C is on, air temp is very hot, and stop/go traffic. Frequently, it's been the fan clutch that was the culprit, and resolved the problem when replaced (for me included). So I'd ask about that.
You mentioned you found the questionnaire, that's a great start.
Did you come across the "expanded" questionnaire? It goes a bit further into detail and is better organzied/grouped.
http://www.vehicross.info/forums/sho...08&postcount=2