Well there are alot of things, I think we can talk about in a sticky post.
One thing that I always thought was a bit of cr)p thinking is the tendency to put 3 kilo nits in a box with a carry handle. Very helpful in one way but then not so helpful when some manufacturers then put the instructions either in a leaflet inside the box leaving the Newbie brewer to make a second trip to the shops to buy all the kit he needs to actually brew the extract.
Another thing that any genuine enthusisat would want to consider is bry hopping the the final beer when kegging it, a few extra hops on a dry basis arn't going to overpower the brew but will improve the overall result.
I guess we could also look at a problems section. Clarity is usually an issue with 1.8 kilo kits, often because of a poor choice of sugar. Also some commentary on replacing sugar in 1.8kilo kits with diastatic malt extract. It's a simple sum 3.0-1.8 really.
Anyway there's a few ideas to get things started.
