Doing this so I have an ongoing list of functioning optimized formulas , keeping it in the community in case it helps someone else. Please feel free to comment with your own, but I'm keeping the most basic of the formulas out of this. Below are just some of the ones that I thought of now, i'll comment more as I use them.
CURRENT PERIOD
this sunday returned as date
=today()-weekday(today())+1
this quarter returned as integer 1-4 standard year
=INT((MONTH(TODAY()) + 2) / 3
NEXT PERIOD
next quarter returned as integer 1-4 standard year (also current quarter if year starts in october)
=IF(INT((MONTH(TODAY()) + 2) / 3) = 4, 1, INT((MONTH(TODAY()) + 2) / 3)+1
next month returned as integer
=if(month(today())=12,1,month(today(
LAST PERIOD
last month returned as integer
=month(date(year(today()),month(today()),1)-1
last quarter standard year returned as integer 1-4 (also current year if year starts in july)
=IF(INT((MONTH(TODAY()) + 2) / 3) = 1, 4, INT((MONTH(TODAY()) + 2) / 3)-1