mister fans - buy a couple if you have a big group
camping stove for bacon and eggs
EL wire and other pretty shit like this for a comfy campsite when everyone's back at 1am
earplugs, for protecting your ears AND helping you sleep. and speaking of sleep...
complete the 1-2 punch with an eye cover... earplugs + eye cover really helps you get that precious extra hour or two until the heat finally wakes you up.
I would go with this Stove
Apologies for the disgusting amazon link.
I know this is also a Coleman, and you've had bad experiences, but this has served me well through ~10 years of cub scout/boy scout camping. Highly recommend it.
As far as what you're looking at, the Tritons are nice, but I've actually had better luck with the one I linked above, it seems to me with Coleman gear, as you go up in price, things tend to break more. I've never heard of Koblenz.
You can find this or something very similar in the outdoor/camping department at Walmart or any other place near you that sells camping supplies.