Alternator sizing
 

Looking to confirm common alternator sizing practice is in S/ST or S/G. I have ready many alternator threads in CR forums, Great information without a defined answer to my question. I utilized Power Master's sizing guide to determine full load at 145A.
What is the prevailing sizing practice?

smaller amperage / lighter alternator to supplement draw from battery?
OR
larger amperage / heavier alternator to facilitate the load while making a pass?

I understand there are personal preferences and difference of opinions. I would like to hear them.
Battery can also be a variable. This site has provided great information on Lithium VS AGM
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