Just as an update as this was a few months ago.
The lager turned out great, not too strong a hop and had a very Eastern European Germanic style to it. It wasn't Stella, but had good flavour and head retention. Trouble is, it was so good, me and the other half drunk it all very quickly lol! I have 2 bottles remaining, I am hanging onto these to add some age to them and see how they develop. It's certainly a batch i will be getting on again very soon, hopefully so I have some ready for Christmas.
As for the Coopers Irish Stout idea, I did that one as well with 300g of chocolate malt and 200g of demerara sugar added to the kit as well as 1kg of dextrose. I brewed that one to 21ltrs also and I have to say, its turned out very well indeed. It has that Guinness flavour but does lack head retention and that creamy Guinness style, but that is hard to replicate at home I believe. It's another one I will be repeating.
Following the stout i went with a Mangrove Jacks Blueberry Cider kit. I followed this one to the instructions with the mangrove jacks recommended fermentables. It's been in the bottle about a month to 6 weeks and it's OK, rather strong, but I'm not 100% sure if I will do it again. It's drinkable and has quite a bit of flavour, just not sure about it yet. It's certainly improving with time so jury is still out on that one.
All in all, I have been really happy so far!