Not sure about your first question without seeing all of your events.
For the second question you wouldn't use an else condition by itself, rather create a variable called WeaponSelect then use the RB press to add to the variable and set the weapon type based on the variable. Personally I'd use a function, as you might want to switch weapons based on other conditions in your game, but there are many ways you can do it.
You can also store your weapon sprites in a single sprite object using different animation frames, or you could add destroy and create events as you liked.
e.g. of function method