Ballast hose sizes

I am going to order my ballast system today. I was looking at fitting sizes. I am going to go with the Johnson pumps.

1. Is there any benefit to going with all 1" fittings and hoses since the pumps are 1/2" NPT and your supposed to get the fitting that converts to 3/4" hose barb?

I was just wondering if the slide over 1" option is really that much faster. It looks like the 3/4" sizing would be significantly cheaper.

2. Will I have to worry about leaks or losing prime with the slip over method on the 1" at the pumps?

3. Do I need to put any type of adhesive on the pump connection with the 1" slip over method or will the hose clamps be reliable?

4. If I go with 1", should I also have the vent/drain be 1"? I assume so, but wanted to verify.

5. If I go with 3/4 for everything, should I go with 1" or 3/4" for the vent/drain?