A larger alt and WP pulley will further underdrive those 2 accessories.

I would not advise it. Esp for the alt, as mine dips at idle as it is currently with just a crank pulley. You could experiment with the WP pulley and see if it stays cool enough. Might be a way to get a bit more out of her, at least in the winter.

You will need a new belt. Im not home right now and wont be for a while or I'd post you up the part number for the new belt.