I've heard a lot of people say about using the US-05 yeast instead of what's supplied with kits.
I haven't tried adding hops or grains to kits yet as I'm new to the hobby/obsession
but I will give it a bash soon enough.
I have a Tooheys Special Lager kit in the cupboard, but I've not heard great things about it. So maybe adding some carefully selected hops/grains might help give the flavour a kick..