Re the grain, there's a heap of info on AHB about this so have a bit pf a search and you should find heaps. I really like this kit, it's quite good just with the kit yeast and 500g LDME, I do add some stuff to it now though to spruce it up. Here's what I'd do in your situation,
22L batch
Coopers EB kit
BE2 if you want a full strenght or half of it for a more to style brew
+1 on adding a bit of grain, and 200g is about where I'd sit
If you want same fresh hop aroma/flavour then I'd go for Styrian Goldings, about 1gL in the fermenter after 3-4 days (I think from memory it's also the hop used in the kit, or the extract of it anyway, not sure)
Yeast, if your sticking to dry then S-04 would be a wise choice, I prefer the Danstar Nottingham or Windsor, but to each their own