Chafing is a very personal thing also affected by your saddle. I’d get one pair of bibs to make sure it works for you first before committing to 4-5 pairs.
I’m a fan of Castelli Free Aero Race 4s. On sale at Competitive Cyclist. Just rode a solo century yesterday with zero chafing issues, and I don’t use chamois cream. Note that these bibs run small. I’m normally a L/XL, but I run XXL with Castelli. Strangely, I run a L with their jerseys and I don’t have a small upper body.
Saddle sores are caused by lack of cleanliness. IMO there’s only one good way to clean “down there” - a mesh ball/shower sponge/loofah with body wash, immediately after any workout. Clean AND exfoliate.
If you can’t shower immediately, use a baby wipe to clean off all the sweat, followed by an antiseptic wipe in the critical areas, followed by another baby wipe to clean off the antiseptic. Then change into boxers immediately.
I treat saddle sores the same way I treat acne. Just gotta be a bit more careful because acne cream can seriously irritate other sensitive areas.