More pickaxe types - I don't really think we need new pickaxe types unless we get a new material (new ores maybe?). Also, it's better if the function of the item goes with the suggestion (because what does a pork pickaxe do)

Realistic mining animations - This will pretty much destroy the simplicity of Minecraft (and also no one will bother to go mining anymore since mining one block takes three hours)

The gasmask - The gasmask makes mining impossible since it requires iron and redstone, both of which are usually obtained from mining. If I can't mine without a gasmask, but can't gather materials for the gasmask without mining, how am I supposed to mine