More than a view
Hakone and Kawaguchiko both work for Fuji-area planning, but they serve different trips.
Choose Hakone
Hakone is better for onsen, ryokan, a softer route break and varied nature between major cities.
Choose Kawaguchiko
Kawaguchiko is better when the Fuji view itself is the main reason and you accept weather-sensitive planning.
Day trip or overnight
An overnight stay reduces pressure. A day trip works only if you accept limited payoff in poor weather.
Make the role clear
Choose rest, view or nature. Do not add a Fuji stop just because it looks good on the route map.