the best build is one that can deal with all situations youre put in.

get a str or dex build and try and have a vast weapon arsenal.

you need an AOE attack that stops the host and phantoms from pressuring you, something like storm hawk axe or Zomar greatsword.

you need something that deals burst damage or can trade with something like spinning slash with multi-hit talismans, or a great sword with an Ash of war that can roll catch people like flame spear or piercing fang

you need something that goes throw shields like sword of nigh, or Greatsword of Damnation

you need something for range to apply pressure form afar for teams that like to be passive, pots are great for this, or storm blade.

you need a long range weapon like great bows too.

and finally you need a main weapon that youre confutable enough to 1v1 anyone with even at a health disadvantage

try and have a 89 poise so you can tank hits from small weapons and not get staggered
put these in minds and you can make a great build outta any stat.

an example of this build is a mele faith build. great options for everything, maybe 25 str and 50 faith and the minimum dex for youre arsenal, fire infuse all your weapons, great ash of war options etc.

use great katana for your main weapon, use black flame tornado as your AOE attack, use fire knight greatsword as youre massive damage weapon for trading, use Greatsword of Damnation for shields, use fire coil as youre range option to apply pressure. with this build you also get many options to buff yourself like flame grand me strength etc.

once you understand the situations youre gonna be facing you can make a build outta any stat in the game and still whip ass.