of course its going to limit their use. The more they cost to make the less people will make and use.
Given that the world is infinite, all resources are therefore also infinite. You don't even need creepers for gunpowder - you can craft it in IC or use UU-Matter.
As for the uranium? It's more abundant than you want to admit - though you did begin your first post by saying people already had a lot of it.
So the material cost of the item is not a concern - they can and will be built and used regardless. It's not as if a lot of them are needed, really. I'm glad you have seen the folly of trying to control the IC nuclear arms race in that fashion.
QuoteI reviewed the explosive power of the nuke and its not so bad actually.
I guess it's relative. A crater that's 53m across and 13m deep is pretty big - and that's what 1 nuke just did on my test world.
Good times, eh?